Program in C for Quick Sort

Write a program in C for Quick Sort

#include <stdio.h>

#define MAXARRAY 10

void quicksort(int arr[], int low, int high);

int main(void)
{
            int array[MAXARRAY] = {0};
            int i = 0;

            /* load some random values into the array */
            for(i = 0; i < MAXARRAY; i++)
                        array[i] = rand() % 100;

            /* print the original array */
            printf("Before quicksort: ");
            for(i = 0; i < MAXARRAY; i++)
            {
                        printf(" %d ", array[i]);
            }
            printf("\n");

            quicksort(array, 0, (MAXARRAY - 1));

            /* print the `quicksorted' array */
            printf("After quicksort: ");
            for(i = 0; i < MAXARRAY; i++) {
                        printf(" %d ", array[i]);
            }
            printf("\n");
           
            return 0;
}

/* sort everything inbetween `low' <-> `high' */
void quicksort(int arr[], int low, int high)
{
            int i = low;
            int j = high;
            int y = 0;
            /* compare value */
            int z = arr[(low + high) / 2];

            /* partition */
            do {
                        /* find member above ... */
                        while(arr[i] < z)
                                    i++;

                        /* find element below ... */
                        while(arr[j] > z)
                                    j--;
           
                        if(i <= j)
                        {
                                    /* swap two elements */
                                    y = arr[i];
                                    arr[i] = arr[j];
                                    arr[j] = y;
                                    i++;
                                    j--;
                        }
            }
            while(i <= j);

            /* recurse */
            if(low < j)
                        quicksort(arr, low, j);

            if(i < high)
                        quicksort(arr, i, high);
}


Post a Comment