mirror of https://github.com/TheAlgorithms/C
60 lines
1.3 KiB
C
60 lines
1.3 KiB
C
/**
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* @file
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* @brief [Insertion sort](https://en.wikipedia.org/wiki/Insertion_sort)
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* algorithm implementation.
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*/
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#include <assert.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <time.h>
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/**
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* Insertion sort algorithm implements
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* @param arr array to be sorted
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* @param size size of array
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*/
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void insertionSort(int *arr, int size)
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{
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for (int i = 1; i < size; i++)
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{
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int j = i - 1;
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int key = arr[i];
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/* Move all elements greater than key to one position */
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while (j >= 0 && key < arr[j])
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{
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arr[j + 1] = arr[j];
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j = j - 1;
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}
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/* Find a correct position for key */
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arr[j + 1] = key;
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}
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}
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/** Test function
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* @returns None
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*/
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static void test()
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{
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const int size = rand() % 500; /* random array size */
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int *arr = (int *)calloc(size, sizeof(int));
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/* generate size random numbers from -50 to 49 */
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for (int i = 0; i < size; i++)
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{
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arr[i] = (rand() % 100) - 50; /* signed random numbers */
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}
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insertionSort(arr, size);
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for (int i = 0; i < size - 1; ++i)
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{
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assert(arr[i] <= arr[i + 1]);
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}
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free(arr);
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}
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int main(int argc, const char *argv[])
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{
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/* Intializes random number generator */
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srand(time(NULL));
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test();
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return 0;
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}
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