quick sort

quicksort.c

#include <stdio.h>

void quicksort(int *arr, int low, int high)
{
    int pivot, i, j, temp;
    if(low < high) {
        pivot = low; // select a pivot element
        i = low;
        j = high;
        while(i < j) {
            // increment i till you get a number greater than the pivot element
            while(arr[i] <= arr[pivot] && i <= high)
                i++;
            // decrement j till you get a number less than the pivot element
            while(arr[j] > arr[pivot] && j >= low)
                j--;
            // if i < j swap the elements in locations i and j
            if(i < j) {
                temp = arr[i];
                arr[i] = arr[j];
                arr[j] = temp;
            }
        }

        // when i >= j it means the j-th position is the correct position
        // of the pivot element, hence swap the pivot element with the
        // element in the j-th position
        temp = arr[j];
        arr[j] = arr[pivot];
        arr[pivot] = temp;
        // Repeat quicksort for the two sub-arrays, one to the left of j
        // and one to the right of j
        quicksort(arr, low, j-1);
        quicksort(arr, j+1, high);
    }
}

int main(int argc, char const *argv[]) {
    int array[] = {99, 98, 97, 96, 95, -100, 100, 0};
    int n = sizeof(array) / sizeof(int);
    quicksort(array, 0, n - 1);
    for (size_t i = 0; i < n; i++) {
        printf("%d\n", array[i]);
    }
    return 0;
}