Recursive Binary Search

#include <stdio.h>

int BinS(int A[], int fir, int l, int key)
{
	int mid;
	if(fir == l)
	{
		if(key == A[fir])
			return fir;
		else
			return 0;
	}
	else
	{
		mid = (fir + l)/2;
		if(key == A[mid])
			return mid;
		else if(key < A[mid])
			return BinS(A, fir, mid-1, key);
		else
			return BinS(A, mid+1, l, key);
	}
}

void main()
{
	int A[50], key, i, size, pos;
	printf("Size : ");
	scanf("%d", &size);
	for(i = 1; i <= size; i++)
		scanf("%d", &A[i]);
	printf("\nEnter key to be searched : ");
	scanf("%d", &key);
	pos = BinS(A, 1, size, key);
	if(pos == 0)
	  printf("\nNot found");
	else
	  printf("\nFound at %d", pos);
}