blog/static/files/pb071/bonuses/03/main.c
Matej Focko 7427475022
chore: transfer all KBs to single one
Signed-off-by: Matej Focko <mfocko@redhat.com>
2022-11-05 15:25:15 +01:00

264 lines
7.2 KiB
C

#include <assert.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/* If you want to see arrays before and after sorting, uncomment next line */
// #define DEBUG_OUTPUT
/**
* @brief Swaps two elements at given addresses of given size.
* @param left Pointer to the first element.
* @param right Pointer to the second element.
* @param size Size of the memory one element takes.
*/
void swap(void *left, void *right, size_t size)
{
/* TODO */
}
/**
* @brief Get index of biggest element in the array.
* @param ptr Pointer to the first element of the array.
* @param count Count of the elements in the array.
* @param size Size of one element in the array.
* @param comp Comparator that is used to decide ordering of the elements.
* @returns Index of the biggest element given the ordering.
*/
size_t maximum(void *ptr, size_t count, size_t size, int (*comp)(const void *, const void *))
{
/* Pseudocode:
* ===========
* max_index <- 0
* FOR i <- 1 TO n - 1 DO
* IF A[i] > A[max_index] THEN
* max_index <- i
* FI
* OD
* RETURN max_index
*/
/* TODO */
return 0;
}
/**
* @brief Sort array in-situ using select-sort.
* @param ptr Pointer to the first element of the array.
* @param count Count of the elements in the array.
* @param size Size of one element in the array.
* @param comp Comparator that is used to decide ordering of the elements.
*/
void select_sort(void *ptr, size_t count, size_t size, int (*comp)(const void *, const void *))
{
/* Pseudocode:
* ===========
* FOR i <- n - 1 DOWNTO 1 DO
* j <- MAXIMUM(A, i + 1)
* SWAP(A, i, j)
* OD
*/
/* TODO */
}
/**
* @brief Compares two integers that are given through generic pointers.
* @param x Pointer to the integer x.
* @param y Pointer to the integer y.
* @returns 0 if x == y, <0 if x < y, >0 otherwise.
*/
static int int_comparator(const void *x, const void *y)
{
/* TODO */
return 1;
}
/**
* @brief Compares two characters by ASCII value.
* @param x Pointer to the character x.
* @param y Pointer to the character y.
* @returns 0 if x == y, <0 if x < y, >0 otherwise.
*/
static int char_comparator(const void *x, const void *y)
{
char x_value = *(const char *) x;
char y_value = *(const char *) y;
return x_value - y_value;
}
/**
* @brief Compares two characters by ASCII value in a reversed order.
* @param x Pointer to the character x.
* @param y Pointer to the character y.
* @returns 0 if x == y, >0 if x < y, <0 otherwise.
*/
static int char_reversed_comparator(const void *x, const void *y)
{
char x_value = *(const char *) x;
char y_value = *(const char *) y;
return y_value - x_value;
}
// #pragma region TESTS
/**
* @brief Check if array is sorted.
* @param ptr Pointer to the first element of the array.
* @param count Count of the elements in the array.
* @param size Size of one element in the array.
* @param comp Comparator that is used to decide ordering of the elements.
*/
static void check_if_sorted(void *ptr, size_t count, size_t size, int (*comp)(const void *, const void *))
{
char *left = ptr;
char *right = (char *) ptr + size;
for (size_t i = 0; i < count - 1; i++) {
assert(comp(left, right) <= 0);
left += size;
right += size;
}
}
#ifdef DEBUG_OUTPUT
/**
* @brief Print numbers from an array.
* @param array Pointer to the first element of the array.
* @param count Count of the elements in the array.
*/
static void print_numbers(int *array, size_t count)
{
for (size_t i = 0; i < count; i++) {
printf(" %d", array[i]);
}
}
#endif
/**
* @brief Run some basic tests on integer arrays.
*/
static void check_int_arrays()
{
/* You are free to add any other examples you like, in case you want to add
* array with more than 10 elements, please adjust the size.
*/
size_t examples_count = 5;
int examples[][10] = {
{ -1, 50, -10, 20, 30, 0, -100 },
{ -100, 0, 30, 20, -10, 50, -1 },
{ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 },
{ -1, -2, -3, -4, -5, -6, -7, -8, -9, -10 },
{ 0, 0, 0, 0, 0, 0, 0, 0 }
};
printf("[TEST] Integer arrays\n");
for (size_t i = 0; i < examples_count; i++) {
size_t count = sizeof(examples[i]) / sizeof(int);
#ifdef DEBUG_OUTPUT
printf("Before sorting:");
print_numbers(examples[i], count);
putchar('\n');
#endif
select_sort(examples[i], count, sizeof(int), int_comparator);
#ifdef DEBUG_OUTPUT
printf("After sorting:");
print_numbers(examples[i], count);
printf("\n\n");
#endif
check_if_sorted(examples[i], count, sizeof(int), int_comparator);
}
printf("[PASS] Tests passed.\n\n");
}
/**
* @brief Run some basic tests on strings. Also with reversed ordering.
*/
static void check_char_arrays()
{
#define MAX_SIZE 20
/* You are free to add any other examples you like, in case you want to add
* strings with more than 10 characters, please adjust the size.
* mind the terminator ;)
*/
const size_t examples_count = 5;
char examples[][MAX_SIZE] = {
"Hello World!",
"hi",
"aloha",
"LET US SORT",
"LeT uS sOrT"
};
printf("[TEST] Char arrays\n");
for (size_t i = 0; i < examples_count; i++) {
size_t count = strlen(examples[i]);
char temp_array[MAX_SIZE];
strncpy(temp_array, examples[i], MAX_SIZE);
select_sort(temp_array, count, 1, char_comparator);
#ifdef DEBUG_OUTPUT
printf("Before sorting: \"%s\"\n", examples[i]);
printf("After sorting: \"%s\"\n\n", temp_array);
#endif
check_if_sorted(temp_array, count, 1, char_comparator);
}
printf("[PASS] Tests passed.\n\n");
printf("[TEST] Char arrays reversed\n");
for (size_t i = 0; i < examples_count; i++) {
size_t count = strlen(examples[i]);
char temp_array[MAX_SIZE];
strncpy(temp_array, examples[i], MAX_SIZE);
select_sort(temp_array, count, 1, char_reversed_comparator);
#ifdef DEBUG_OUTPUT
printf("Before sorting: \"%s\"\n", examples[i]);
printf("After sorting: \"%s\"\n\n", temp_array);
#endif
check_if_sorted(temp_array, count, 1, char_reversed_comparator);
}
printf("[PASS] Tests passed.\n\n");
#undef MAX_SIZE
}
static void annotate(const char *description, bool result)
{
printf("[TEST] %s\n", description);
assert(result);
printf("[PASS] Test passed.\n\n");
}
static void check_int_comparator()
{
int a = 5, b = -10, c = -10;
annotate("Test comparator for: a > b", int_comparator(&a, &b) > 0);
annotate("Test comparator for: b < a", int_comparator(&b, &a) < 0);
annotate("Test comparator for: b = c", int_comparator(&b, &c) == 0);
annotate("Test comparator for: a = a", int_comparator(&a, &a) == 0);
annotate("Test comparator for: b = b", int_comparator(&b, &b) == 0);
annotate("Test comparator for: c = c", int_comparator(&c, &c) == 0);
}
// #pragma endregion TESTS
int main(void)
{
/* Neither of those tests check for bad behaviour, like overwriting array
* with elements satisfying ordering. **I** check those :scheming:
*/
check_int_comparator();
check_int_arrays();
check_char_arrays();
return 0;
}