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feat: don't reference FI MU subjects by their codes
Signed-off-by: Matej Focko <mfocko@redhat.com>
This commit is contained in:
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232 changed files with 225 additions and 191 deletions
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@ -1,5 +1,5 @@
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---
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---
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id: ib002-intro
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id: algorithms-intro
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title: Introduction
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title: Introduction
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slug: /
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slug: /
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---
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---
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@ -4,17 +4,17 @@ title: Vague postconditions and proving correctness of algorithms
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description: |
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description: |
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Debugging and testing with precise postconditions.
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Debugging and testing with precise postconditions.
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tags:
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tags:
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- python
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- python
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- testing
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- testing
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- postconditions
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- postconditions
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- sorting
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- sorting
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last_update:
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last_update:
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date: 2021-03-18
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date: 2021-03-18
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---
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---
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## Introduction
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## Introduction
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[Source code](pathname:///files/ib002/algorithms-correctness/postcondition-ambiguity/test_sort.py) used later on.
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[Source code](pathname:///files/algorithms/algorithms-correctness/postcondition-ambiguity/test_sort.py) used later on.
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## Implementation of select sort from the exercises
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## Implementation of select sort from the exercises
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@ -4,11 +4,11 @@ title: Time complexity of ‹extend›
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description: |
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description: |
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How to make inefficient algorithm unknowingly.
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How to make inefficient algorithm unknowingly.
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tags:
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tags:
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- c
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- c
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- python
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- python
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- dynamic array
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- dynamic array
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- time complexity
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- time complexity
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- recursion
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- recursion
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last_update:
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last_update:
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date: 2021-03-31
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date: 2021-03-31
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---
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---
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@ -86,8 +86,8 @@ As we could observe in the example above, `extend` iterates over all of the elem
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Consider constructing of this list:
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Consider constructing of this list:
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
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
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
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
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Let us assume that you extend the result with the list that you get from the recursive call.
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Let us assume that you extend the result with the list that you get from the recursive call.
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@ -108,8 +108,8 @@ If the recursion had bigger depth and/or more elements, it would iterate through
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There is an example of dynamic array:
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There is an example of dynamic array:
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- [interface (`dynlist.h`)](pathname:///files/ib002/time-complexity/extend/dynlist.h)
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- [interface (`dynlist.h`)](pathname:///files/algorithms/time-complexity/extend/dynlist.h)
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- [implementation (`dynlist.c`)](pathname:///files/ib002/time-complexity/extend/dynlist.c)
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- [implementation (`dynlist.c`)](pathname:///files/algorithms/time-complexity/extend/dynlist.c)
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For the sake of _Algorithms and Data Structures I_ we consider `APPEND` operation, i.e. adding the element to the end of the list, to have time complexity $\mathcal{O}(1)$ (**amortized**; which is out of the scope of IB002).
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For the sake of _Algorithms and Data Structures I_ we consider `APPEND` operation, i.e. adding the element to the end of the list, to have time complexity $\mathcal{O}(1)$ (**amortized**; which is out of the scope of IB002).
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@ -4,15 +4,15 @@ title: Recursion and backtracking with Robot Karel
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description: |
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description: |
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A problem with too many restrictions.
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A problem with too many restrictions.
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tags:
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tags:
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- python
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- python
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- karel
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- karel
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- recursion
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- recursion
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- backtracking
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- backtracking
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last_update:
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last_update:
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date: 2022-11-29
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date: 2022-11-29
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---
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---
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- [Sources](pathname:///files/ib002/recursion/karel-1.tar.gz)
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- [Sources](pathname:///files/algorithms/recursion/karel-1.tar.gz)
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## Introduction
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## Introduction
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@ -81,7 +81,7 @@ your mind. Ideally:
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- Write down a nested list of the problems, e.g.
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- Write down a nested list of the problems, e.g.
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:::info Example
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:::info Example
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Problem: I want to find out whether the display on smartphone should rotate.
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Problem: I want to find out whether the display on smartphone should rotate.
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@ -94,6 +94,7 @@ your mind. Ideally:
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- How can I process it?
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- How can I process it?
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:::
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:::
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- Write down list of problems that can happen, e.g.
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- Write down list of problems that can happen, e.g.
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:::info Example continued
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:::info Example continued
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@ -105,6 +106,7 @@ your mind. Ideally:
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- What if my formulas are wrong?
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- What if my formulas are wrong?
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:::
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:::
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- Write down **anything** you consider important to solving the problem, e.g.
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- Write down **anything** you consider important to solving the problem, e.g.
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:::info Example continued once again
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:::info Example continued once again
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@ -164,4 +166,4 @@ it out by yourself without any influence of “example solution”.
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If you want to get any feedback, feel free to mail me your solution (including
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If you want to get any feedback, feel free to mail me your solution (including
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all the steps that lead to your final solution, if you wish to get feedback on
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all the steps that lead to your final solution, if you wish to get feedback on
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those too).
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those too).
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@ -4,13 +4,13 @@ title: Introduction to dynamic programming
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description: |
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description: |
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Solving a problem in different ways.
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Solving a problem in different ways.
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tags:
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tags:
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- java
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- java
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- recursion
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- recursion
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- exponential
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- exponential
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- greedy
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- greedy
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- dynamic-programming
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- dynamic-programming
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- top-down-dp
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- top-down-dp
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- bottom-up-dp
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- bottom-up-dp
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last_updated:
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last_updated:
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date: 2023-08-17
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date: 2023-08-17
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---
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---
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@ -26,6 +26,7 @@ We are given a 2D array of integers and we are to find the _slide down_.
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_Slide down_ is a maximum sum of consecutive numbers from the top to the bottom.
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_Slide down_ is a maximum sum of consecutive numbers from the top to the bottom.
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Let's have a look at few examples. Consider the following pyramid:
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Let's have a look at few examples. Consider the following pyramid:
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```
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```
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3
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3
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7 4
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7 4
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```
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```
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This pyramid has following slide down:
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This pyramid has following slide down:
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```
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```
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*3
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*3
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*7 4
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*7 4
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@ -44,6 +46,7 @@ This pyramid has following slide down:
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And its value is `23`.
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And its value is `23`.
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We can also have a look at a _bigger_ example:
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We can also have a look at a _bigger_ example:
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```
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```
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75
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75
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95 64
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95 64
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@ -61,6 +64,7 @@ We can also have a look at a _bigger_ example:
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63 66 4 68 89 53 67 30 73 16 69 87 40 31
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63 66 4 68 89 53 67 30 73 16 69 87 40 31
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4 62 98 27 23 9 70 98 73 93 38 53 60 4 23
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4 62 98 27 23 9 70 98 73 93 38 53 60 4 23
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```
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```
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Slide down in this case is equal to `1074`.
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Slide down in this case is equal to `1074`.
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## Solving the problem
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## Solving the problem
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will output `true`/`false` based on the expected output of our algorithm. Any
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will output `true`/`false` based on the expected output of our algorithm. Any
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other differences will lie only in the solutions of the problem. You can see the
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other differences will lie only in the solutions of the problem. You can see the
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`main` here:
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`main` here:
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```java
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```java
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public static void main(String[] args) {
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public static void main(String[] args) {
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System.out.print("Test #1: ");
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System.out.print("Test #1: ");
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@ -141,6 +146,7 @@ public static int longestSlideDown(int[][] pyramid) {
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```
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```
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As you can see, we have 2 overloads:
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As you can see, we have 2 overloads:
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```java
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```java
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int longestSlideDown(int[][] pyramid);
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int longestSlideDown(int[][] pyramid);
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int longestSlideDown(int[][] pyramid, int row, int col);
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int longestSlideDown(int[][] pyramid, int row, int col);
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@ -162,6 +168,7 @@ really is a naïve solution, the time complexity is pretty bad. Let's find the
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worst case scenario.
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worst case scenario.
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Let's start with the first overload:
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Let's start with the first overload:
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```java
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```java
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public static int longestSlideDown(int[][] pyramid) {
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public static int longestSlideDown(int[][] pyramid) {
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return longestSlideDown(pyramid, 0, 0);
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return longestSlideDown(pyramid, 0, 0);
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@ -208,6 +215,7 @@ choosing the under and right both. They are separate computations though, so we
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are branching from each call of `longestSlideDown`, unless it's a base case.
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are branching from each call of `longestSlideDown`, unless it's a base case.
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What does that mean for us then? We basically get
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What does that mean for us then? We basically get
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$$
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$$
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T(y) =
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T(y) =
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\begin{cases}
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\begin{cases}
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@ -217,6 +225,7 @@ T(y) =
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$$
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$$
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That looks rather easy to compute, isn't it? If you sum it up, you'll get:
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That looks rather easy to compute, isn't it? If you sum it up, you'll get:
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$$
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$$
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T(rows) \in \mathcal{O}(2^{rows})
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T(rows) \in \mathcal{O}(2^{rows})
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$$
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$$
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@ -256,6 +265,7 @@ optimal option at the moment.
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We can try to adjust the naïve solution. The most problematic part are the
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We can try to adjust the naïve solution. The most problematic part are the
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recursive calls. Let's apply the greedy approach there:
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recursive calls. Let's apply the greedy approach there:
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```java
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```java
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public static int longestSlideDown(int[][] pyramid, int row, int col) {
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public static int longestSlideDown(int[][] pyramid, int row, int col) {
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if (row == pyramid.length - 1) {
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if (row == pyramid.length - 1) {
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@ -282,6 +292,7 @@ we simply go left.
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We have switched from _adding the maximum_ to _following the “bigger” path_, so
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We have switched from _adding the maximum_ to _following the “bigger” path_, so
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we improved the time complexity tremendously. We just go down the pyramid all
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we improved the time complexity tremendously. We just go down the pyramid all
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the way to the bottom. Therefore we are getting:
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the way to the bottom. Therefore we are getting:
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$$
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$$
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\mathcal{O}(rows)
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\mathcal{O}(rows)
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$$
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$$
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@ -291,6 +302,7 @@ We have managed to convert our exponential solution into a linear one.
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### Running the tests
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### Running the tests
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However, if we run the tests, we notice that the second test failed:
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However, if we run the tests, we notice that the second test failed:
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```
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```
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Test #1: passed
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Test #1: passed
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Test #2: failed
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Test #2: failed
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@ -301,6 +313,7 @@ algorithms are not the ideal solution to **all** problems. In this case there
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may be a solution that is bigger than the one found using the greedy algorithm.
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may be a solution that is bigger than the one found using the greedy algorithm.
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Imagine the following pyramid:
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Imagine the following pyramid:
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|
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```
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```
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1
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1
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2 3
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2 3
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@ -310,6 +323,7 @@ Imagine the following pyramid:
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```
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```
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We start at the top:
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We start at the top:
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1. Current cell: `1`, we can choose from `2` and `3`, `3` looks better, so we
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1. Current cell: `1`, we can choose from `2` and `3`, `3` looks better, so we
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choose it.
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choose it.
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2. Current cell: `3`, we can choose from `6` and `7`, `7` looks better, so we
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2. Current cell: `3`, we can choose from `6` and `7`, `7` looks better, so we
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@ -429,6 +443,7 @@ that!
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Overall we are doing the same things for almost[^2] all of the positions within
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Overall we are doing the same things for almost[^2] all of the positions within
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the pyramid:
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the pyramid:
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1. We calculate and store it (using the partial results stored in cache). This
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1. We calculate and store it (using the partial results stored in cache). This
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is done only once.
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is done only once.
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@ -452,8 +467,9 @@ the pyramid:
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:::
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:::
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Our final upper bound of this work is therefore $\log_2{n}$.
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Our final upper bound of this work is therefore $\log_2{n}$.
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2. We retrieve it from the cache. Same as in first point, but only twice, so we
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2. We retrieve it from the cache. Same as in first point, but only twice, so we
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get $2 \cdot \log_2{n}$.
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get $2 \cdot \log_2{n}$.
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:::caution
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:::caution
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@ -465,6 +481,7 @@ Okay, we have evaluated work done for each of the cells in the pyramid and now
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we need to put it together.
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we need to put it together.
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Let's split the time complexity of our solution into two operands:
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Let's split the time complexity of our solution into two operands:
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|
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$$
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$$
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\mathcal{O}(r + s)
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\mathcal{O}(r + s)
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$$
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$$
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@ -473,6 +490,7 @@ $r$ will represent the _actual_ calculation of the cells and $s$ will represent
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the additional retrievals on top of the calculation.
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the additional retrievals on top of the calculation.
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We calculate the values only **once**, therefore we can safely agree on:
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We calculate the values only **once**, therefore we can safely agree on:
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|
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$$
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$$
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\begin{align*}
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\begin{align*}
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r &= n \cdot \log{n} \\
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r &= n \cdot \log{n} \\
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@ -482,6 +500,7 @@ $$
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What about the $s$ though? Key observation here is the fact that we have 2
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What about the $s$ though? Key observation here is the fact that we have 2
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lookups on the tree in each of them **and** we do it twice, cause each cell has
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lookups on the tree in each of them **and** we do it twice, cause each cell has
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at most 2 parents:
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at most 2 parents:
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|
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$$
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$$
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\begin{align*}
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\begin{align*}
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s &= n \cdot 2 \cdot \left( 2 \cdot \log{n} \right) \\
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s &= n \cdot 2 \cdot \left( 2 \cdot \log{n} \right) \\
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@ -496,6 +515,7 @@ of the results. This is not entirely true, since we have included the
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`.containsKey()` and `.get()` from the `return` statement in the second part.
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`.containsKey()` and `.get()` from the `return` statement in the second part.
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If we were to represent this more precisely, we could've gone with:
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If we were to represent this more precisely, we could've gone with:
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|
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$$
|
$$
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\begin{align*}
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\begin{align*}
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r &= 3 \cdot n \cdot \log{n} \\
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r &= 3 \cdot n \cdot \log{n} \\
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@ -512,6 +532,7 @@ doesn't really matter.
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|
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And so our final time complexity for the whole _top-down dynamic programming_
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And so our final time complexity for the whole _top-down dynamic programming_
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approach is:
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approach is:
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|
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$$
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$$
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\mathcal{O}(r + s) \\
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\mathcal{O}(r + s) \\
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\mathcal{O}(n \cdot \log{n} + 4 \cdot n \cdot \log{n}) \\
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\mathcal{O}(n \cdot \log{n} + 4 \cdot n \cdot \log{n}) \\
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@ -531,11 +552,13 @@ down. At the end we get the final result for `new Position(0, 0)`, so we need to
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compute everything below.
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compute everything below.
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|
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That's how we obtain:
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That's how we obtain:
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|
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$$
|
$$
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\mathcal{O}(n)
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\mathcal{O}(n)
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$$
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$$
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|
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$n$ represents the total amount of cells in the pyramid, i.e.
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$n$ represents the total amount of cells in the pyramid, i.e.
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|
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$$
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$$
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\sum_{y=0}^{\mathtt{pyramid.length} - 1} \mathtt{pyramid}\left[y\right]\mathtt{.length}
|
\sum_{y=0}^{\mathtt{pyramid.length} - 1} \mathtt{pyramid}\left[y\right]\mathtt{.length}
|
||||||
$$
|
$$
|
||||||
|
@ -553,6 +576,7 @@ number.
|
||||||
|
|
||||||
Yes, it can! Try to think about a way, how can you minimize the memory
|
Yes, it can! Try to think about a way, how can you minimize the memory
|
||||||
complexity of this approach. I'll give you a hint:
|
complexity of this approach. I'll give you a hint:
|
||||||
|
|
||||||
$$
|
$$
|
||||||
\mathcal{O}(rows)
|
\mathcal{O}(rows)
|
||||||
$$
|
$$
|
||||||
|
@ -578,6 +602,7 @@ to implement right from the beginning.
|
||||||
:::
|
:::
|
||||||
|
|
||||||
Let's see how we can implement it:
|
Let's see how we can implement it:
|
||||||
|
|
||||||
```java
|
```java
|
||||||
public static int longestSlideDown(int[][] pyramid) {
|
public static int longestSlideDown(int[][] pyramid) {
|
||||||
// In the beginning we declare new array. At this point it is easier to just
|
// In the beginning we declare new array. At this point it is easier to just
|
||||||
|
@ -647,6 +672,7 @@ the best **overall** result I can achieve.
|
||||||
Time complexity of this solution is rather simple. We allocate an array for the
|
Time complexity of this solution is rather simple. We allocate an array for the
|
||||||
rows and then for each row, we copy it and adjust the partial results. Doing
|
rows and then for each row, we copy it and adjust the partial results. Doing
|
||||||
this we get:
|
this we get:
|
||||||
|
|
||||||
$$
|
$$
|
||||||
\mathcal{O}(rows + 2n)
|
\mathcal{O}(rows + 2n)
|
||||||
$$
|
$$
|
||||||
|
@ -658,6 +684,7 @@ once.
|
||||||
|
|
||||||
We're allocating an array for the pyramid **again** for our partial results, so
|
We're allocating an array for the pyramid **again** for our partial results, so
|
||||||
we get:
|
we get:
|
||||||
|
|
||||||
$$
|
$$
|
||||||
\mathcal{O}(n)
|
\mathcal{O}(n)
|
||||||
$$
|
$$
|
||||||
|
@ -695,11 +722,11 @@ successor and represents the way we can enhance the existing implementation.
|
||||||
:::info source
|
:::info source
|
||||||
|
|
||||||
You can find source code referenced in the text
|
You can find source code referenced in the text
|
||||||
[here](pathname:///files/ib002/recursion/pyramid-slide-down.tar.gz).
|
[here](pathname:///files/algorithms/recursion/pyramid-slide-down.tar.gz).
|
||||||
|
|
||||||
:::
|
:::
|
||||||
|
|
||||||
[^1]: cause why not, right!?
|
[^1]: cause why not, right!?
|
||||||
[^2]: except the bottom row
|
[^2]: except the bottom row
|
||||||
[^3]: definitely not an RHCP reference :wink:
|
[^3]: definitely not an RHCP reference :wink:
|
||||||
[^4]: one was not correct, thus the quotes
|
[^4]: one was not correct, thus the quotes
|
|
@ -4,9 +4,9 @@ title: Použití červeno-černých stromů
|
||||||
description: |
|
description: |
|
||||||
Ukázka použití červeno-černých stromů v standardních knižnicích známých jazyků.
|
Ukázka použití červeno-černých stromů v standardních knižnicích známých jazyků.
|
||||||
tags:
|
tags:
|
||||||
- balanced trees
|
- balanced trees
|
||||||
- red-black trees
|
- red-black trees
|
||||||
- applications
|
- applications
|
||||||
last_update:
|
last_update:
|
||||||
date: 2022-04-05
|
date: 2022-04-05
|
||||||
---
|
---
|
|
@ -4,8 +4,8 @@ title: On the rules of the red-black tree
|
||||||
description: |
|
description: |
|
||||||
Shower thoughts on the rules of the red-black tree.
|
Shower thoughts on the rules of the red-black tree.
|
||||||
tags:
|
tags:
|
||||||
- red-black trees
|
- red-black trees
|
||||||
- balanced trees
|
- balanced trees
|
||||||
last_update:
|
last_update:
|
||||||
date: 2023-06-10
|
date: 2023-06-10
|
||||||
---
|
---
|
||||||
|
@ -18,6 +18,7 @@ each of the red-black tree rules and try to change, break and contemplate about
|
||||||
them.
|
them.
|
||||||
|
|
||||||
We expect that you are familiar with the following set of the rules[^1]:
|
We expect that you are familiar with the following set of the rules[^1]:
|
||||||
|
|
||||||
1. Every node is either red or black.
|
1. Every node is either red or black.
|
||||||
2. The root is black.
|
2. The root is black.
|
||||||
3. Every leaf (`nil`) is black.
|
3. Every leaf (`nil`) is black.
|
||||||
|
@ -55,13 +56,13 @@ my child would be colored red.
|
||||||
Example of a red-black tree that keeps count of black nodes on paths to the
|
Example of a red-black tree that keeps count of black nodes on paths to the
|
||||||
leaves follows:
|
leaves follows:
|
||||||
|
|
||||||

|

|
||||||

|

|
||||||
|
|
||||||
We mark the _black heights_ in superscript. You can see that all leaves have the
|
We mark the _black heights_ in superscript. You can see that all leaves have the
|
||||||
black height equal to $1$. Let's take a look at some of the interesting cases:
|
black height equal to $1$. Let's take a look at some of the interesting cases:
|
||||||
|
|
||||||
* If we take a look at the node with $\text{key} = 9$, we can see that it is
|
- If we take a look at the node with $\text{key} = 9$, we can see that it is
|
||||||
coloured red and its black height is 1, because it is a leaf.
|
coloured red and its black height is 1, because it is a leaf.
|
||||||
|
|
||||||
Let's look at its parent (node with $\text{key} = 8$). On its left side it has
|
Let's look at its parent (node with $\text{key} = 8$). On its left side it has
|
||||||
|
@ -71,12 +72,12 @@ black height equal to $1$. Let's take a look at some of the interesting cases:
|
||||||
We can clearly see that if a node has the same black height as its parent, it
|
We can clearly see that if a node has the same black height as its parent, it
|
||||||
is a red node.
|
is a red node.
|
||||||
|
|
||||||
* Now let's take a look at the root with $\text{key} = 3$. It has a black height
|
- Now let's take a look at the root with $\text{key} = 3$. It has a black height
|
||||||
of 3. Both of its children are black nodes and have black height of 2.
|
of 3. Both of its children are black nodes and have black height of 2.
|
||||||
|
|
||||||
We can see that if a node has its height 1 lower than its parent, it is a black
|
We can see that if a node has its height 1 lower than its parent, it is a black
|
||||||
node.
|
node.
|
||||||
|
|
||||||
The reasoning behind it is rather simple, we count the black nodes all the way
|
The reasoning behind it is rather simple, we count the black nodes all the way
|
||||||
to the leaves, therefore if my parent has a higher black height, it means that
|
to the leaves, therefore if my parent has a higher black height, it means that
|
||||||
on the path from me to my parent there is a black node, but the only node added
|
on the path from me to my parent there is a black node, but the only node added
|
||||||
|
@ -95,6 +96,7 @@ This rule might seem like a very important one, but overall is not. You can safe
|
||||||
omit this rule, but you also need to deal with the consequences.
|
omit this rule, but you also need to deal with the consequences.
|
||||||
|
|
||||||
Let's refresh our memory with the algorithm of _insert fixup_:
|
Let's refresh our memory with the algorithm of _insert fixup_:
|
||||||
|
|
||||||
```
|
```
|
||||||
WHILE z.p.color == Red
|
WHILE z.p.color == Red
|
||||||
IF z.p == z.p.p.left
|
IF z.p == z.p.p.left
|
||||||
|
@ -138,17 +140,17 @@ black root property.
|
||||||
If we decide to omit this condition, we need to address it in the pseudocodes
|
If we decide to omit this condition, we need to address it in the pseudocodes
|
||||||
accordingly.
|
accordingly.
|
||||||
|
|
||||||
| Usual algorithm with black root | Allowing red root |
|
| Usual algorithm with black root | Allowing red root |
|
||||||
| :-----------------------------: | :---------------: |
|
| :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------: | :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------: |
|
||||||
|  |  |
|
|  |  |
|
||||||
|  |  |
|
|  |  |
|
||||||
|  |  |
|
|  |  |
|
||||||
|  |  |
|
|  |  |
|
||||||
|  |  |
|
|  |  |
|
||||||
|  |  |
|
|  |  |
|
||||||
|  |  |
|
|  |  |
|
||||||
|  |  |
|
|  |  |
|
||||||
|  |  |
|
|  |  |
|
||||||
|
|
||||||
## 3ª Every leaf (`nil`) is black.
|
## 3ª Every leaf (`nil`) is black.
|
||||||
|
|
||||||
|
@ -157,8 +159,8 @@ some other way? Let's go through some of the possible ways I can look at this an
|
||||||
how would they affect the other rules and balancing.
|
how would they affect the other rules and balancing.
|
||||||
|
|
||||||
We will experiment with the following tree:
|
We will experiment with the following tree:
|
||||||

|

|
||||||

|

|
||||||
|
|
||||||
We should start by counting the black nodes from root to the `nil` leaves based
|
We should start by counting the black nodes from root to the `nil` leaves based
|
||||||
on the rules. We have multiple similar paths, so we will pick only the interesting
|
on the rules. We have multiple similar paths, so we will pick only the interesting
|
||||||
|
@ -170,11 +172,11 @@ ones.
|
||||||
3. What happens if we do not count the `nil` leaves, but consider nodes with at
|
3. What happens if we do not count the `nil` leaves, but consider nodes with at
|
||||||
least one `nil` descendant as leaves?
|
least one `nil` descendant as leaves?
|
||||||
|
|
||||||
| path | black nodes | 1ª idea | 2ª idea | 3ª idea |
|
| path | black nodes | 1ª idea | 2ª idea | 3ª idea |
|
||||||
| ------------------------: | ----------: | ------: | ------: | ------: |
|
| ------------------------: | ----------: | ------: | ------: | ------: |
|
||||||
| `3 → 1 → 0 → nil` | 4 | 3 | 4 | 3 |
|
| `3 → 1 → 0 → nil` | 4 | 3 | 4 | 3 |
|
||||||
| `3 → 5 → 7 → 8 → nil` | 4 | 3 | - | 3 |
|
| `3 → 5 → 7 → 8 → nil` | 4 | 3 | - | 3 |
|
||||||
| `3 → 5 → 7 → 8 → 9 → nil` | 4 | 3 | 4 | 3 |
|
| `3 → 5 → 7 → 8 → 9 → nil` | 4 | 3 | 4 | 3 |
|
||||||
|
|
||||||
First idea is very easy to execute and it is also very easy to argue about its
|
First idea is very easy to execute and it is also very easy to argue about its
|
||||||
correctness. It is correct, because we just subtract one from each of the paths.
|
correctness. It is correct, because we just subtract one from each of the paths.
|
||||||
|
@ -208,7 +210,7 @@ functions:
|
||||||
|
|
||||||
When we have a look at the algorithms that are used for fixing up the red-black
|
When we have a look at the algorithms that are used for fixing up the red-black
|
||||||
tree after an insertion or deletion, we will notice that all the algorithms need
|
tree after an insertion or deletion, we will notice that all the algorithms need
|
||||||
is the color of the node.
|
is the color of the node.
|
||||||
|
|
||||||
> How come it is the only thing that we need?
|
> How come it is the only thing that we need?
|
||||||
> How come such naïve thing can be enough?
|
> How come such naïve thing can be enough?
|
||||||
|
@ -232,15 +234,15 @@ import TabItem from '@theme/TabItem';
|
||||||
<Tabs>
|
<Tabs>
|
||||||
<TabItem value="enforcing" label="Enforcing this rule">
|
<TabItem value="enforcing" label="Enforcing this rule">
|
||||||
|
|
||||||

|

|
||||||

|

|
||||||
|
|
||||||
</TabItem>
|
</TabItem>
|
||||||
|
|
||||||
<TabItem value="omitting" label="Omitting this rule">
|
<TabItem value="omitting" label="Omitting this rule">
|
||||||
|
|
||||||

|

|
||||||

|

|
||||||
|
|
||||||
</TabItem>
|
</TabItem>
|
||||||
</Tabs>
|
</Tabs>
|
||||||
|
@ -262,6 +264,7 @@ An important observation here is the fact that the red-black tree is a
|
||||||
:::
|
:::
|
||||||
|
|
||||||
Enforcing this rule (together with the 4th rule) keeps the tree balanced:
|
Enforcing this rule (together with the 4th rule) keeps the tree balanced:
|
||||||
|
|
||||||
1. 4th rule makes sure we can't “hack” this requirement.
|
1. 4th rule makes sure we can't “hack” this requirement.
|
||||||
2. This rule ensures that we have “similar”[^2] length to each of the leaves.
|
2. This rule ensures that we have “similar”[^2] length to each of the leaves.
|
||||||
|
|
||||||
|
@ -279,4 +282,4 @@ complexity for the operations, but having more relaxed rules.
|
||||||
:::
|
:::
|
||||||
|
|
||||||
[^1]: CORMEN, Thomas. Introduction to algorithms. Cambridge, Mass: MIT Press, 2009. isbn 9780262033848.
|
[^1]: CORMEN, Thomas. Introduction to algorithms. Cambridge, Mass: MIT Press, 2009. isbn 9780262033848.
|
||||||
[^2]: red nodes still exist
|
[^2]: red nodes still exist
|
|
@ -4,17 +4,17 @@ title: Iterative algorithms via iterators
|
||||||
description: |
|
description: |
|
||||||
Iterative DFS using iterators.
|
Iterative DFS using iterators.
|
||||||
tags:
|
tags:
|
||||||
- csharp
|
- csharp
|
||||||
- graphs
|
- graphs
|
||||||
- iterators
|
- iterators
|
||||||
- iterative
|
- iterative
|
||||||
last_update:
|
last_update:
|
||||||
date: 2021-05-18
|
date: 2021-05-18
|
||||||
---
|
---
|
||||||
|
|
||||||
## Introduction
|
## Introduction
|
||||||
|
|
||||||
- [Source code used later on.](pathname:///files/ib002/graphs/iterative-and-iterators.tar.gz)
|
- [Source code used later on.](pathname:///files/algorithms/graphs/iterative-and-iterators.tar.gz)
|
||||||
|
|
||||||
As we have talked on the seminar, iterative approach to implementing DFS is not very intuitive and is a very easy way how to create an incorrect implementation.
|
As we have talked on the seminar, iterative approach to implementing DFS is not very intuitive and is a very easy way how to create an incorrect implementation.
|
||||||
|
|
||||||
|
@ -171,7 +171,6 @@ begin
|
||||||
end DFS;
|
end DFS;
|
||||||
```
|
```
|
||||||
|
|
||||||
|
|
||||||
( The way we manipulate with the iterators is closest to the C# implementation. Apart from the `Iterator` thing :) In case you tried to implement it in C++, you would more than likely need to change the check, since you would get first successor right at the beginning )
|
( The way we manipulate with the iterators is closest to the C# implementation. Apart from the `Iterator` thing :) In case you tried to implement it in C++, you would more than likely need to change the check, since you would get first successor right at the beginning )
|
||||||
|
|
||||||
So here we don't keep indices, but the iterators. We can also check existence of other successors easily: by the iterator moving after the last successor.
|
So here we don't keep indices, but the iterators. We can also check existence of other successors easily: by the iterator moving after the last successor.
|
|
@ -4,8 +4,8 @@ title: Distance boundaries from BFS tree on undirected graphs
|
||||||
description: |
|
description: |
|
||||||
Short explanation of distance boundaries deduced from a BFS tree.
|
Short explanation of distance boundaries deduced from a BFS tree.
|
||||||
tags:
|
tags:
|
||||||
- graphs
|
- graphs
|
||||||
- bfs
|
- bfs
|
||||||
last_update:
|
last_update:
|
||||||
date: 2022-04-30
|
date: 2022-04-30
|
||||||
---
|
---
|
||||||
|
@ -21,13 +21,13 @@ As we have talked on the seminar, if we construct from some vertex $u$ BFS tree
|
||||||
|
|
||||||
Consider the following graph:
|
Consider the following graph:
|
||||||
|
|
||||||

|

|
||||||

|

|
||||||
|
|
||||||
We run BFS from the vertex $a$ and obtain the following BFS tree:
|
We run BFS from the vertex $a$ and obtain the following BFS tree:
|
||||||
|
|
||||||

|

|
||||||

|

|
||||||
|
|
||||||
Let's consider pair of vertices $e$ and $h$. For them we can safely lay, from the BFS tree, following properties:
|
Let's consider pair of vertices $e$ and $h$. For them we can safely lay, from the BFS tree, following properties:
|
||||||
|
|
||||||
|
@ -42,9 +42,8 @@ Let's keep the same graph, but break the lower bound, i.e. I have gotten a lower
|
||||||
|
|
||||||
Now the more important question, is there a shorter path in that graph? The answer is no, there's no shorter path than the one with length $2$. So what can we do about it? We'll add an edge to have a shorter path. Now we have gotten a lower bound of $2$, which means the only shorter path we can construct has $1$ edge and that is ‹$e, h$› (no intermediary vertices). Let's do this!
|
Now the more important question, is there a shorter path in that graph? The answer is no, there's no shorter path than the one with length $2$. So what can we do about it? We'll add an edge to have a shorter path. Now we have gotten a lower bound of $2$, which means the only shorter path we can construct has $1$ edge and that is ‹$e, h$› (no intermediary vertices). Let's do this!
|
||||||
|
|
||||||

|

|
||||||

|

|
||||||
|
|
||||||
|
|
||||||
Okay, so we have a graph that breaks the rule we have laid. However, we need to run BFS to obtain the new BFS tree, since we have changed the graph.
|
Okay, so we have a graph that breaks the rule we have laid. However, we need to run BFS to obtain the new BFS tree, since we have changed the graph.
|
||||||
|
|
||||||
|
@ -56,8 +55,8 @@ Do we need to run BFS after **every** change?
|
||||||
|
|
||||||
:::
|
:::
|
||||||
|
|
||||||

|

|
||||||

|

|
||||||
|
|
||||||
Oops, we have gotten a new BFS tree, that has a height difference of 1.
|
Oops, we have gotten a new BFS tree, that has a height difference of 1.
|
||||||
|
|
|
@ -1,5 +1,5 @@
|
||||||
---
|
---
|
||||||
id: ib015-intro
|
id: automata-intro
|
||||||
title: Introduction
|
title: Introduction
|
||||||
slug: /
|
slug: /
|
||||||
---
|
---
|
|
@ -1,5 +1,5 @@
|
||||||
---
|
---
|
||||||
id: ib111-intro
|
id: c-intro
|
||||||
title: Introduction
|
title: Introduction
|
||||||
slug: /
|
slug: /
|
||||||
---
|
---
|
|
@ -30,7 +30,7 @@ Details can be found in the doxygen comments included in the source files.
|
||||||
|
|
||||||
## Light version (`main_light.c`)
|
## Light version (`main_light.c`)
|
||||||
|
|
||||||
[Source](pathname:///files/pb071/bonuses/03/main_light.c)
|
[Source](pathname:///files/c/bonuses/03/main_light.c)
|
||||||
|
|
||||||
For the light version you have 3 functions to finish:
|
For the light version you have 3 functions to finish:
|
||||||
|
|
||||||
|
@ -40,7 +40,7 @@ For the light version you have 3 functions to finish:
|
||||||
|
|
||||||
## Full fat version (`main.c`)
|
## Full fat version (`main.c`)
|
||||||
|
|
||||||
[Source](pathname:///files/pb071/bonuses/03/main.c)
|
[Source](pathname:///files/c/bonuses/03/main.c)
|
||||||
|
|
||||||
For the full fat version you have 4 functions to implement:
|
For the full fat version you have 4 functions to implement:
|
||||||
|
|
||||||
|
@ -61,6 +61,7 @@ passed a _function pointer_ to the comparator that you use for comparing the
|
||||||
respective elements in the passed in array.
|
respective elements in the passed in array.
|
||||||
|
|
||||||
If we take the parameter from one of the functions from the skeleton:
|
If we take the parameter from one of the functions from the skeleton:
|
||||||
|
|
||||||
```c
|
```c
|
||||||
int (*comp)(const void *, const void *)
|
int (*comp)(const void *, const void *)
|
||||||
```
|
```
|
||||||
|
@ -91,6 +92,7 @@ Ideally create a directory `seminar-bonuses` in the root of your repository with
|
||||||
bonuses in their own subdirectories.
|
bonuses in their own subdirectories.
|
||||||
|
|
||||||
Structure of your repository can look like this:
|
Structure of your repository can look like this:
|
||||||
|
|
||||||
```
|
```
|
||||||
.
|
.
|
||||||
├── bonuses
|
├── bonuses
|
|
@ -22,7 +22,7 @@ or just by submitting an issue [here](https://gitlab.fi.muni.cz/xfocko/kb/-/issu
|
||||||
|
|
||||||
For this bonus you can get 3 K₡ and another 0.5 K₡ for the bonus part of it.
|
For this bonus you can get 3 K₡ and another 0.5 K₡ for the bonus part of it.
|
||||||
|
|
||||||
[Source](pathname:///files/pb071/bonuses/04.tar.gz)
|
[Source](pathname:///files/c/bonuses/04.tar.gz)
|
||||||
|
|
||||||
## Introduction
|
## Introduction
|
||||||
|
|
|
@ -7,7 +7,7 @@ description: |
|
||||||
|
|
||||||
For this bonus you can get at maximum 2.5 K₡.
|
For this bonus you can get at maximum 2.5 K₡.
|
||||||
|
|
||||||
[Source](pathname:///files/pb071/bonuses/05-06.tar.gz)
|
[Source](pathname:///files/c/bonuses/05-06.tar.gz)
|
||||||
|
|
||||||
## Introduction
|
## Introduction
|
||||||
|
|
|
@ -7,7 +7,7 @@ description: |
|
||||||
|
|
||||||
# 8th seminar bonus assignment
|
# 8th seminar bonus assignment
|
||||||
|
|
||||||
[Source](pathname:///files/pb071/bonuses/08.tar.gz)
|
[Source](pathname:///files/c/bonuses/08.tar.gz)
|
||||||
|
|
||||||
## Introduction
|
## Introduction
|
||||||
|
|
||||||
|
@ -118,7 +118,7 @@ nil
|
||||||
</td>
|
</td>
|
||||||
<td>
|
<td>
|
||||||
|
|
||||||

|

|
||||||
|
|
||||||
</td>
|
</td>
|
||||||
</tr></table>
|
</tr></table>
|
|
@ -5,7 +5,7 @@ description: |
|
||||||
Finding bugs in a hangman.
|
Finding bugs in a hangman.
|
||||||
---
|
---
|
||||||
|
|
||||||
[Source](pathname:///files/pb071/bonuses/10.tar.gz)
|
[Source](pathname:///files/c/bonuses/10.tar.gz)
|
||||||
|
|
||||||
## Introduction
|
## Introduction
|
||||||
|
|
||||||
|
@ -86,7 +86,7 @@ As we have talked about on the seminar, I suggest you to follow
|
||||||
_Test-Driven Development_
|
_Test-Driven Development_
|
||||||
in this case.
|
in this case.
|
||||||
|
|
||||||

|

|
||||||
|
|
||||||
In our current scenario we are already in the stage of refactoring and fixing the
|
In our current scenario we are already in the stage of refactoring and fixing the
|
||||||
bugs. Therefore try to follow this succession of steps:
|
bugs. Therefore try to follow this succession of steps:
|
|
@ -11,16 +11,16 @@ last_update:
|
||||||
|
|
||||||
:::caution Exam environment
|
:::caution Exam environment
|
||||||
|
|
||||||
* During the exam you will be provided with a barebone _exam session_ on the
|
- During the exam you will be provided with a barebone _exam session_ on the
|
||||||
_faculty computers_.
|
_faculty computers_.
|
||||||
* In browser you are only allowed to have the following tabs open:
|
- In browser you are only allowed to have the following tabs open:
|
||||||
* [C documentation](https://en.cppreference.com)
|
- [C documentation](https://en.cppreference.com)
|
||||||
* page containing the assignment
|
- page containing the assignment
|
||||||
* You **are not** allowed to use your own source code, e.g. prepared beforehand
|
- You **are not** allowed to use your own source code, e.g. prepared beforehand
|
||||||
or from the seminars.
|
or from the seminars.
|
||||||
* You have **5 minutes** to read through the assignment and ask any follow-up
|
- You have **5 minutes** to read through the assignment and ask any follow-up
|
||||||
questions should be there something unclear.
|
questions should be there something unclear.
|
||||||
* You have **60 minutes** to work on the assignment, afterward your work will be
|
- You have **60 minutes** to work on the assignment, afterward your work will be
|
||||||
discussed with your seminar tutor.
|
discussed with your seminar tutor.
|
||||||
|
|
||||||
:::
|
:::
|
||||||
|
@ -41,11 +41,12 @@ can see only two commands being used:
|
||||||
1. `cd ‹somewhere›` that changes the current working directory.
|
1. `cd ‹somewhere›` that changes the current working directory.
|
||||||
|
|
||||||
At the beginning you start in the root of the filesystem (i.e. `/`).
|
At the beginning you start in the root of the filesystem (i.e. `/`).
|
||||||
|
|
||||||
You are **guaranteed** that `‹somewhere›` is:
|
You are **guaranteed** that `‹somewhere›` is:
|
||||||
* `.` that is a current working directory (i.e. does nothing),
|
|
||||||
* `..` that moves you up one level (in case you are in `/`, does nothing), or
|
- `.` that is a current working directory (i.e. does nothing),
|
||||||
* is a valid directory in the current working directory.
|
- `..` that moves you up one level (in case you are in `/`, does nothing), or
|
||||||
|
- is a valid directory in the current working directory.
|
||||||
|
|
||||||
:::caution
|
:::caution
|
||||||
|
|
||||||
|
@ -87,6 +88,7 @@ $ ls
|
||||||
```
|
```
|
||||||
|
|
||||||
For this input, you will get following file system:
|
For this input, you will get following file system:
|
||||||
|
|
||||||
```
|
```
|
||||||
- / (dir, size=48381165)
|
- / (dir, size=48381165)
|
||||||
- a (dir, size=94853)
|
- a (dir, size=94853)
|
||||||
|
@ -108,14 +110,14 @@ For this input, you will get following file system:
|
||||||
|
|
||||||
Your program should support 2 switches:
|
Your program should support 2 switches:
|
||||||
|
|
||||||
* `-gt ‹min_size›` that will print out suspiciously big files.
|
- `-gt ‹min_size›` that will print out suspiciously big files.
|
||||||
* `-f ‹total_size› ‹min_unused›` that will print out a file to be deleted.
|
- `-f ‹total_size› ‹min_unused›` that will print out a file to be deleted.
|
||||||
|
|
||||||
### `-gt ‹min_size›`
|
### `-gt ‹min_size›`
|
||||||
|
|
||||||
With this switch you are provided one additional argument:
|
With this switch you are provided one additional argument:
|
||||||
|
|
||||||
* `min_size` that is the lower bound (inclusive) for size of any file or
|
- `min_size` that is the lower bound (inclusive) for size of any file or
|
||||||
directory that is supposed to be listed.
|
directory that is supposed to be listed.
|
||||||
|
|
||||||
When your program is being run with this switch, it is is supposed to print out
|
When your program is being run with this switch, it is is supposed to print out
|
||||||
|
@ -125,13 +127,14 @@ all files **and** directories that are bigger than the provided `min_size`.
|
||||||
|
|
||||||
With this switch you are provided two additional arguments:
|
With this switch you are provided two additional arguments:
|
||||||
|
|
||||||
* `total_size` that is a total size of the filesystem[^2].
|
- `total_size` that is a total size of the filesystem[^2].
|
||||||
* `min_unused` that is a minimum of free space required for an upgrade.
|
- `min_unused` that is a minimum of free space required for an upgrade.
|
||||||
|
|
||||||
Your program should find **exactly one** file or a directory that is of the
|
Your program should find **exactly one** file or a directory that is of the
|
||||||
smallest size, but big enough to free enough space for the upgrade to proceed.
|
smallest size, but big enough to free enough space for the upgrade to proceed.
|
||||||
|
|
||||||
In other words, if that file or directory is deleted, following should hold:
|
In other words, if that file or directory is deleted, following should hold:
|
||||||
|
|
||||||
$$
|
$$
|
||||||
\mathtt{total\_size} - \mathtt{used} \geq \mathtt{min\_unused}
|
\mathtt{total\_size} - \mathtt{used} \geq \mathtt{min\_unused}
|
||||||
$$
|
$$
|
||||||
|
@ -151,19 +154,19 @@ program from the shell like
|
||||||
|
|
||||||
## Requirements and notes
|
## Requirements and notes
|
||||||
|
|
||||||
* Define **structures** (and **enumerations**, if applicable) for the parsed
|
- Define **structures** (and **enumerations**, if applicable) for the parsed
|
||||||
information from the files.
|
information from the files.
|
||||||
* For keeping the “records”, use some **dynamic** data structure.
|
- For keeping the “records”, use some **dynamic** data structure.
|
||||||
* Don't forget to consider pros and cons of using _specific_ data structures
|
- Don't forget to consider pros and cons of using _specific_ data structures
|
||||||
before going through implementing.
|
before going through implementing.
|
||||||
* You **are not required** to produce 1:1 output to the provided examples, they
|
- You **are not required** to produce 1:1 output to the provided examples, they
|
||||||
are just a hint to not waste your time tinkering with a user experience.
|
are just a hint to not waste your time tinkering with a user experience.
|
||||||
* If any of the operations on the input files should fail,
|
- If any of the operations on the input files should fail,
|
||||||
**you are expected to** handle the situation _accordingly_.
|
**you are expected to** handle the situation _accordingly_.
|
||||||
* Failures of any other common functions (e.g. functions used for memory
|
- Failures of any other common functions (e.g. functions used for memory
|
||||||
management) should be handled in **the same way** as they were in the
|
management) should be handled in **the same way** as they were in the
|
||||||
homeworks and seminars.
|
homeworks and seminars.
|
||||||
* Your program **must free** all the resources before exiting.
|
- Your program **must free** all the resources before exiting.
|
||||||
|
|
||||||
[^1]: Also applies to Fedora, but… we use arch btw :wink:
|
[^1]: Also applies to Fedora, but… we use arch btw :wink:
|
||||||
[^2]: duh!
|
[^2]: duh!
|
|
@ -11,16 +11,16 @@ last_update:
|
||||||
|
|
||||||
:::caution Exam environment
|
:::caution Exam environment
|
||||||
|
|
||||||
* During the exam you will be provided with a barebone _exam session_ on the
|
- During the exam you will be provided with a barebone _exam session_ on the
|
||||||
_faculty computers_.
|
_faculty computers_.
|
||||||
* In browser you are only allowed to have the following tabs open:
|
- In browser you are only allowed to have the following tabs open:
|
||||||
* [C documentation](https://en.cppreference.com)
|
- [C documentation](https://en.cppreference.com)
|
||||||
* page containing the assignment
|
- page containing the assignment
|
||||||
* You **are not** allowed to use your own source code, e.g. prepared beforehand
|
- You **are not** allowed to use your own source code, e.g. prepared beforehand
|
||||||
or from the seminars.
|
or from the seminars.
|
||||||
* You have **5 minutes** to read through the assignment and ask any follow-up
|
- You have **5 minutes** to read through the assignment and ask any follow-up
|
||||||
questions should be there something unclear.
|
questions should be there something unclear.
|
||||||
* You have **60 minutes** to work on the assignment, afterward your work will be
|
- You have **60 minutes** to work on the assignment, afterward your work will be
|
||||||
discussed with your seminar tutor.
|
discussed with your seminar tutor.
|
||||||
|
|
||||||
:::
|
:::
|
||||||
|
@ -31,11 +31,11 @@ print out summary based on the input data. Your contributions to the society are
|
||||||
very much appreciated and may (or may not) be used for (each or none) of the
|
very much appreciated and may (or may not) be used for (each or none) of the
|
||||||
following purposes[^1]:
|
following purposes[^1]:
|
||||||
|
|
||||||
* stalking people leaving and coming back home,
|
- stalking people leaving and coming back home,
|
||||||
* retroactively making people pay for the parking,
|
- retroactively making people pay for the parking,
|
||||||
* providing evidence of people speeding on highways,
|
- providing evidence of people speeding on highways,
|
||||||
* tracking people that don't pay tolls, or
|
- tracking people that don't pay tolls, or
|
||||||
* convict employees leaving the work prematurely.
|
- convict employees leaving the work prematurely.
|
||||||
|
|
||||||
## Format of the input file
|
## Format of the input file
|
||||||
|
|
||||||
|
@ -45,10 +45,10 @@ specify `-` (i.e. `stdin`) as the path.
|
||||||
|
|
||||||
Each “scan” (i.e. reading) of the cameras consists of the following data:
|
Each “scan” (i.e. reading) of the cameras consists of the following data:
|
||||||
|
|
||||||
* _camera ID_: non-negative integer identifying a camera
|
- _camera ID_: non-negative integer identifying a camera
|
||||||
* _plate_: string of unknown length that can consist of any characters apart
|
- _plate_: string of unknown length that can consist of any characters apart
|
||||||
from whitespace
|
from whitespace
|
||||||
* _timestamp_: date and time of the scan as an unsigned integer (represented as
|
- _timestamp_: date and time of the scan as an unsigned integer (represented as
|
||||||
a UNIX time)
|
a UNIX time)
|
||||||
|
|
||||||
:::tip
|
:::tip
|
||||||
|
@ -114,7 +114,6 @@ when outputting the date and time.
|
||||||
|
|
||||||
:::
|
:::
|
||||||
|
|
||||||
|
|
||||||
:::tip
|
:::tip
|
||||||
|
|
||||||
For a better readability you can include one more newline after the last line
|
For a better readability you can include one more newline after the last line
|
||||||
|
@ -133,46 +132,46 @@ And it will produce an output:
|
||||||
|
|
||||||
*** ABC-12-34 ***
|
*** ABC-12-34 ***
|
||||||
25: Fri Oct 1 10:50:56 2021
|
25: Fri Oct 1 10:50:56 2021
|
||||||
|
|
||||||
10: Sat Oct 1 09:18:32 2022
|
10: Sat Oct 1 09:18:32 2022
|
||||||
16: Sat Oct 1 09:23:32 2022
|
16: Sat Oct 1 09:23:32 2022
|
||||||
|
|
||||||
19: Sat Oct 1 23:27:29 2022
|
19: Sat Oct 1 23:27:29 2022
|
||||||
|
|
||||||
*** EL9-987 ***
|
*** EL9-987 ***
|
||||||
11: Thu Mar 23 04:15:38 2023
|
11: Thu Mar 23 04:15:38 2023
|
||||||
|
|
||||||
*** Foo-666 ***
|
*** Foo-666 ***
|
||||||
2: Thu May 4 05:14:42 2023
|
2: Thu May 4 05:14:42 2023
|
||||||
|
|
||||||
*** TryToCatchMe ***
|
*** TryToCatchMe ***
|
||||||
42: Wed Dec 21 07:00:19 2022
|
42: Wed Dec 21 07:00:19 2022
|
||||||
42: Wed Dec 21 07:00:19 2022
|
42: Wed Dec 21 07:00:19 2022
|
||||||
1234: Wed Dec 21 07:00:19 2022
|
1234: Wed Dec 21 07:00:19 2022
|
||||||
|
|
||||||
*** XYZ-98-76 ***
|
*** XYZ-98-76 ***
|
||||||
289: Mon Oct 10 17:40:17 2022
|
289: Mon Oct 10 17:40:17 2022
|
||||||
|
|
||||||
*** YouShould-not-pLaCe-4ny-expectations%on^the(input ***
|
*** YouShould-not-pLaCe-4ny-expectations%on^the(input ***
|
||||||
69: Sat Apr 1 02:13:14 2023
|
69: Sat Apr 1 02:13:14 2023
|
||||||
|
|
||||||
*** YourMum ***
|
*** YourMum ***
|
||||||
42: Thu May 4 05:14:42 2023
|
42: Thu May 4 05:14:42 2023
|
||||||
|
|
||||||
## Requirements and notes
|
## Requirements and notes
|
||||||
|
|
||||||
* Define **structures** (and **enumerations**, if applicable) for the parsed
|
- Define **structures** (and **enumerations**, if applicable) for the parsed
|
||||||
information from the files.
|
information from the files.
|
||||||
* For keeping the “records”, use some **dynamic** data structure.
|
- For keeping the “records”, use some **dynamic** data structure.
|
||||||
* Don't forget to consider pros and cons of using _specific_ data structures
|
- Don't forget to consider pros and cons of using _specific_ data structures
|
||||||
before going through implementing.
|
before going through implementing.
|
||||||
* You **are not required** to produce 1:1 output to the provided examples, they
|
- You **are not required** to produce 1:1 output to the provided examples, they
|
||||||
are just a hint to not waste your time tinkering with a user experience.
|
are just a hint to not waste your time tinkering with a user experience.
|
||||||
* If any of the operations on the input files should fail,
|
- If any of the operations on the input files should fail,
|
||||||
**you are expected to** handle the situation _accordingly_.
|
**you are expected to** handle the situation _accordingly_.
|
||||||
* Failures of any other common functions (e.g. functions used for memory
|
- Failures of any other common functions (e.g. functions used for memory
|
||||||
management) should be handled in **the same way** as they were in the
|
management) should be handled in **the same way** as they were in the
|
||||||
homeworks and seminars.
|
homeworks and seminars.
|
||||||
* Your program **must free** all the resources before exiting.
|
- Your program **must free** all the resources before exiting.
|
||||||
|
|
||||||
[^1]: Subject to NDA.
|
[^1]: Subject to NDA.
|
|
@ -1,5 +1,5 @@
|
||||||
---
|
---
|
||||||
id: pb071-intro
|
id: cpp-intro
|
||||||
title: Introduction
|
title: Introduction
|
||||||
slug: /
|
slug: /
|
||||||
---
|
---
|
|
@ -106,7 +106,7 @@ contained.
|
||||||
|
|
||||||
Since frag creates a lot of support files (majority of them are dotfiles, i.e.
|
Since frag creates a lot of support files (majority of them are dotfiles, i.e.
|
||||||
hidden files), I recommend you to use following
|
hidden files), I recommend you to use following
|
||||||
[gitignore](pathname:///files/pb161/environment/gitignore) configuration that
|
[gitignore](pathname:///files/cpp/environment/gitignore) configuration that
|
||||||
should cover most of the scenarios.
|
should cover most of the scenarios.
|
||||||
|
|
||||||
### pre-commit ([link](https://pre-commit.com/))
|
### pre-commit ([link](https://pre-commit.com/))
|
|
@ -1,7 +1,7 @@
|
||||||
// @ts-check
|
// @ts-check
|
||||||
// Note: type annotations allow type checking and IDEs autocompletion
|
// Note: type annotations allow type checking and IDEs autocompletion
|
||||||
|
|
||||||
const {themes} = require("prism-react-renderer");
|
const { themes } = require("prism-react-renderer");
|
||||||
const lightCodeTheme = themes.vsLight;
|
const lightCodeTheme = themes.vsLight;
|
||||||
const darkCodeTheme = themes.dracula;
|
const darkCodeTheme = themes.dracula;
|
||||||
|
|
||||||
|
@ -10,9 +10,9 @@ const katex = require("rehype-katex");
|
||||||
|
|
||||||
require("dotenv").config();
|
require("dotenv").config();
|
||||||
|
|
||||||
class Subject {
|
class Docs {
|
||||||
constructor(subject, description) {
|
constructor(path, description) {
|
||||||
this.subject = subject;
|
this.path = path;
|
||||||
this.description = description;
|
this.description = description;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
@ -20,9 +20,9 @@ class Subject {
|
||||||
return [
|
return [
|
||||||
"@docusaurus/plugin-content-docs",
|
"@docusaurus/plugin-content-docs",
|
||||||
{
|
{
|
||||||
id: this.subject,
|
id: this.path,
|
||||||
path: this.subject,
|
path: this.path,
|
||||||
routeBasePath: this.subject,
|
routeBasePath: this.path,
|
||||||
sidebarPath: require.resolve("./sidebars.js"),
|
sidebarPath: require.resolve("./sidebars.js"),
|
||||||
showLastUpdateTime: true,
|
showLastUpdateTime: true,
|
||||||
editUrl: "https://github.com/mfocko/blog/tree/main",
|
editUrl: "https://github.com/mfocko/blog/tree/main",
|
||||||
|
@ -35,27 +35,27 @@ class Subject {
|
||||||
navbar() {
|
navbar() {
|
||||||
return {
|
return {
|
||||||
type: "doc",
|
type: "doc",
|
||||||
docId: `${this.subject}-intro`,
|
docId: `${this.path}-intro`,
|
||||||
docsPluginId: this.subject,
|
docsPluginId: this.path,
|
||||||
label: `${this.subject.toUpperCase()}: ${this.description}`,
|
label: `${this.description}`,
|
||||||
};
|
};
|
||||||
}
|
}
|
||||||
|
|
||||||
footer() {
|
footer() {
|
||||||
return {
|
return {
|
||||||
label: `${this.subject.toUpperCase()}: ${this.description}`,
|
label: `${this.description}`,
|
||||||
to: this.subject,
|
to: this.path,
|
||||||
};
|
};
|
||||||
}
|
}
|
||||||
}
|
}
|
||||||
|
|
||||||
const subjects = [
|
const subjects = [
|
||||||
new Subject("ib002", "Algorithms"),
|
new Docs("algorithms", "Algorithms"),
|
||||||
// new Subject("ib015", "Non-imperative programming"),
|
// new Docs("functional", "Non-imperative programming"),
|
||||||
// new Subject("ib110", "Introduction to informatics"),
|
// new Docs("automata", "Formal languages and automata"),
|
||||||
// new Subject("ib111", "Foundations of programming"),
|
// new Docs("foundations", "Foundations of programming"),
|
||||||
new Subject("pb071", "C"),
|
new Docs("c", "C"),
|
||||||
new Subject("pb161", "C++"),
|
new Docs("cpp", "C++"),
|
||||||
];
|
];
|
||||||
|
|
||||||
/** @type {import('@docusaurus/types').Config} */
|
/** @type {import('@docusaurus/types').Config} */
|
||||||
|
|
5
foundations/00-intro.md
Normal file
5
foundations/00-intro.md
Normal file
|
@ -0,0 +1,5 @@
|
||||||
|
---
|
||||||
|
id: foundations-intro
|
||||||
|
title: Introduction
|
||||||
|
slug: /
|
||||||
|
---
|
|
@ -1,5 +1,5 @@
|
||||||
---
|
---
|
||||||
id: ib110-intro
|
id: functional-intro
|
||||||
title: Introduction
|
title: Introduction
|
||||||
slug: /
|
slug: /
|
||||||
---
|
---
|
|
@ -1,5 +0,0 @@
|
||||||
---
|
|
||||||
id: pb161-intro
|
|
||||||
title: Introduction
|
|
||||||
slug: /
|
|
||||||
---
|
|
|
@ -14,4 +14,4 @@ graph {
|
||||||
d -- h
|
d -- h
|
||||||
|
|
||||||
h -- j
|
h -- j
|
||||||
}
|
}
|
|
@ -15,4 +15,4 @@ graph {
|
||||||
d -- h
|
d -- h
|
||||||
|
|
||||||
h -- j
|
h -- j
|
||||||
}
|
}
|
|
@ -10,4 +10,4 @@ digraph {
|
||||||
b -> h
|
b -> h
|
||||||
|
|
||||||
i -> d
|
i -> d
|
||||||
}
|
}
|
|
@ -9,4 +9,4 @@ digraph {
|
||||||
e -> j
|
e -> j
|
||||||
|
|
||||||
i -> d
|
i -> d
|
||||||
}
|
}
|
|
@ -44,4 +44,4 @@ digraph {
|
||||||
"Node(value=6, rank=0)" -> "nil9"
|
"Node(value=6, rank=0)" -> "nil9"
|
||||||
"Node(value=9, rank=0)" -> "nil10"
|
"Node(value=9, rank=0)" -> "nil10"
|
||||||
"Node(value=9, rank=0)" -> "nil11"
|
"Node(value=9, rank=0)" -> "nil11"
|
||||||
}
|
}
|
|
@ -44,4 +44,4 @@ digraph {
|
||||||
"Node(value=6, rank=0)" -> "nil9"
|
"Node(value=6, rank=0)" -> "nil9"
|
||||||
"Node(value=9, rank=0)" -> "nil10"
|
"Node(value=9, rank=0)" -> "nil10"
|
||||||
"Node(value=9, rank=0)" -> "nil11"
|
"Node(value=9, rank=0)" -> "nil11"
|
||||||
}
|
}
|
|
@ -31,4 +31,4 @@ digraph {
|
||||||
"Node(value=4, rank=0)" -> "nil7"
|
"Node(value=4, rank=0)" -> "nil7"
|
||||||
"Node(value=7, rank=0)" -> "nil8"
|
"Node(value=7, rank=0)" -> "nil8"
|
||||||
"Node(value=7, rank=0)" -> "nil9"
|
"Node(value=7, rank=0)" -> "nil9"
|
||||||
}
|
}
|
|
@ -6,7 +6,7 @@ digraph {
|
||||||
"Node(value=0, rank=0)" [label="0"]; #done
|
"Node(value=0, rank=0)" [label="0"]; #done
|
||||||
"Node(value=2, rank=0)" [label="2"]; #done
|
"Node(value=2, rank=0)" [label="2"]; #done
|
||||||
"Node(value=5, rank=1)" [label="5"]; #done
|
"Node(value=5, rank=1)" [label="5"]; #done
|
||||||
|
|
||||||
|
|
||||||
"nil2" [label="", color=none]
|
"nil2" [label="", color=none]
|
||||||
"nil3" [label="", color=none]
|
"nil3" [label="", color=none]
|
||||||
|
@ -34,7 +34,7 @@ digraph {
|
||||||
"Node(value=4, rank=0)" -> "nil7"
|
"Node(value=4, rank=0)" -> "nil7"
|
||||||
"Node(value=7, rank=0)" -> "nil8"
|
"Node(value=7, rank=0)" -> "nil8"
|
||||||
"Node(value=7, rank=0)" -> "8" [color="red"]
|
"Node(value=7, rank=0)" -> "8" [color="red"]
|
||||||
|
|
||||||
"8" -> "nil9"
|
"8" -> "nil9"
|
||||||
"8" -> "nil10"
|
"8" -> "nil10"
|
||||||
}
|
}
|
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Loading…
Add table
Reference in a new issue