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141 lines
3.2 KiB
C
141 lines
3.2 KiB
C
#include <assert.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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/* If you want to see arrays before and after sorting, uncomment next line */
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// #define DEBUG_OUTPUT
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/**
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* @brief Swaps two elements at given addresses.
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* @param left Pointer to the first element.
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* @param right Pointer to the second element.
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*/
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void swap(int *left, int *right)
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{
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/* TODO */
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}
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/**
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* @brief Get index of biggest element in the array.
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* @param ptr Pointer to the first element of the array.
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* @param count Count of the elements in the array.
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* @returns Index of the biggest element given the ordering.
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*/
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size_t maximum(int *ptr, size_t count)
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{
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/* Pseudocode:
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* ===========
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* max_index <- 0
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* FOR i <- 1 TO n - 1 DO
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* IF A[i] > A[max_index] THEN
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* max_index <- i
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* FI
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* OD
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* RETURN max_index
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*/
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/* TODO */
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return 0;
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}
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/**
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* @brief Sort array in-situ using select-sort.
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* @param ptr Pointer to the first element of the array.
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* @param count Count of the elements in the array.
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*/
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void select_sort(int *ptr, size_t count)
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{
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/* Pseudocode:
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* ===========
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* FOR i <- n - 1 DOWNTO 1 DO
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* j <- MAXIMUM(A, i + 1)
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* SWAP(A, i, j)
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* OD
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*/
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/* TODO */
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}
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// #pragma region TESTS
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/**
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* @brief Check if array is sorted.
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* @param ptr Pointer to the first element of the array.
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* @param count Count of the elements in the array.
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*/
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static void check_if_sorted(int *ptr, size_t count)
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{
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int *left = ptr;
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int *right = ptr + 1;
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for (size_t i = 0; i < count - 1; i++) {
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assert(*left <= *right);
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left++;
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right++;
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}
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}
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#ifdef DEBUG_OUTPUT
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/**
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* @brief Print numbers from an array.
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* @param array Pointer to the first element of the array.
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* @param count Count of the elements in the array.
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*/
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static void print_numbers(int *array, size_t count)
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{
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for (size_t i = 0; i < count; i++) {
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printf(" %d", array[i]);
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}
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}
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#endif
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/**
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* @brief Run some basic tests on integer arrays.
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*/
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static void check_int_arrays()
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{
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/* You are free to add any other examples you like, in case you want to add
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* array with more than 10 elements, please adjust the size.
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*/
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size_t examples_count = 5;
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int examples[][10] = {
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{ -1, 50, -10, 20, 30, 0, -100 },
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{ -100, 0, 30, 20, -10, 50, -1 },
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{ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 },
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{ -1, -2, -3, -4, -5, -6, -7, -8, -9, -10 },
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{ 0, 0, 0, 0, 0, 0, 0, 0 }
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};
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printf("[TEST] Integer arrays\n");
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for (size_t i = 0; i < examples_count; i++) {
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size_t count = sizeof(examples[i]) / sizeof(int);
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#ifdef DEBUG_OUTPUT
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printf("Before sorting:");
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print_numbers(examples[i], count);
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putchar('\n');
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#endif
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select_sort(examples[i], count);
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#ifdef DEBUG_OUTPUT
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printf("After sorting:");
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print_numbers(examples[i], count);
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printf("\n\n");
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#endif
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check_if_sorted(examples[i], count);
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}
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printf("[PASS] Tests passed.\n\n");
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}
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// #pragma endregion TESTS
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int main(void)
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{
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/* Neither of those tests check for bad behaviour, like overwriting array
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* with elements satisfying ordering. **I** check those :scheming:
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*/
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check_int_arrays();
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return 0;
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}
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