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: Time Limit Exceeded)

#include <stdio.h>
#include <ctype.h>
#include <stdlib.h>

int main()
{
	int n, x, cnt, f;

	while (1) {
		scanf("%d %d\n", &n, &x);
		if (n == 0 && x == 0) break;

		cnt = 0;
		for (int i = n; i > 0; --i) {
			for (int j = i; j>0; ++j) {
				if (i <= ((n - i) % j)) cnt++;
			}
		}
		printf("%d", cnt);
	}

	return 0;
}