Qcksort, 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);
}

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