Problem:
How many ways?

Write a program which identifies the number of combinations of three integers which satisfy the following conditions:

You should select three distinct integers from 1 to n.

A total sum of the three integers is x.

For example, there are two combinations for n = 5 and x = 9.

1 + 3 + 5 = 9

2 + 3 + 4 = 9

Input

The input consists of multiple datasets. For each dataset, two integers n and x are given in a line.

The input ends with two zeros for n and x respectively. Your program should not process for these terminal symbols.

Constraints

3 ≤ n ≤ 100

0 ≤ x ≤ 300

Output

For each dataset, print the number of combinations in a line.

Sample Input

5 9
0 0

Sample Output

2

Note

      解説

Solution in C (judge verdict: Accepted)

#include <stdio.h>
 
int main()
{
	int i,j,k;
	int n,x;
	int count;
	while(1){
		scanf("%d %d", &n, &x);
		if(n==0&&x==0){
			break;
		}
		count=0;
		for(i=1; i<=n; i++){
			for(j=1; j<=n; j++){
				for(k=1; k<=n; k++){
					if(i+j+k==x){
						if(i!=j&&j!=k&&k!=i){
							count++;
						}
					}
				}
			}
		}
		printf("%d\n", count/6);
	}
	return 0;
}