Quick sort simple c code

#include<stdio.h>

void swap (int a[], int left, int right)
{
 int temp;
 temp=a[left];
 a[left]=a[right];
 a[right]=temp;
}//end swap

void quicksort( int a[], int low, int high )
{
 int pivot;
 // Termination condition!
 if ( high > low )
 {
  pivot = partition( a, low, high );
  quicksort( a, low, pivot-1 );
  quicksort( a, pivot+1, high );
 }
} //end quicksort

int partition( int a[], int low, int high )
{
 int left, right;
 int pivot_item;
 int pivot = left = low;
 pivot_item = a[low];
 right = high;
 while ( left < right )
 {
  // Move left while item < pivot
  while( a[left] <= pivot_item )
   left++;
  // Move right while item > pivot
  while( a[right] > pivot_item )
   right--;
  if ( left < right )
   swap(a,left,right);
 }
 // right is final position for the pivot
 a[low] = a[right];
 a[right] = pivot_item;
 return right;
}//end partition

// void quicksort(int a[], int, int);
void printarray(int a[], int);

int main()
{
 int a[50], i, n;
 printf("\nEnter no. of elements: ");
 scanf("%d", &n);
 printf("\nEnter the elements: \n");
 for (i=0; i<n; i++)
  scanf ("%d", &a[i]);
 printf("\nUnsorted elements: \n");
 printarray(a,n);
 quicksort(a,0,n-1);
 printf("\nSorted elements: \n");
 printarray(a,n);

}//end main


void printarray(int a[], int n)
{
 int i;
 for (i=0; i<n; i++)
  printf(" %d ", a[i]);
 printf("\n");
}//end printarray