#include <stdio.h>
int A (int x, int y)
{
	if (x==0)
		return y+1;
		else if (y==0)
			A(x-1,1);
			else
				A(x-1,A(x,y-1));
}
int main ()
{
	int x, y;
	printf("Input x: "); scanf("%d", &x);
	printf("Input y: "); scanf("%d", &y);
	printf("%d",A (x,y));
	return 0;
}