C program to implement Quick Sort

Quick sort algorithm is based on divide and conquer strategy. In a quick sort we take the one element called as pivot,then we list all the smaller elements than pivot, and greater than pivot. after partitioning we have pivot in the final position. After recursively sorting the partition array, we get the sorted elements

Example of C program to implement Quick Sort

#include <stdio.h>
void quick_sort(int [], int, int);
int partition(int [], int, int);
main()
{
 int a[50], n, i;
 printf("nEnter size of an array: ");
 scanf("%d", &n);
 printf("nEnter elements of an array:n");
 for(i=0; i<n; i++)
 scanf("%d", &a[i]);
 quick_sort(a, 0, n-1);
 printf("nnAfter sorting:n");
 for(i=0; i<n; i++)
 printf("n%d", a[i]);
 getch();
}

void quick_sort(int a[], int beg, int end)
{
 int x;
 if (beg < end)
 {
  x = partition(a, beg, end);
  quick_sort(a, beg, x-1);
  quick_sort(a, x+1, end);
 }
}

int partition(int a[], int beg, int end)
{
 int loc = beg, temp;
 while (1)
 {
 while (a[loc]<=a[end] && loc!=end) /* Scan from right to left */
 end--;
 if (loc == end)
  return loc;
 temp = a[loc];
 a[loc] = a[end];
 a[end] = temp;
 loc = end;
 while (a[loc]>=a[beg] && loc!=beg) /* Scan from left to right */
  beg++;
 if (loc == beg)
  return loc;
 temp = a[loc];
 a[loc] = a[beg];
 a[beg] = temp;
 loc = beg;
 }
}