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 n, x;
    do
    {
         scanf("%d %d", &n, &x);
        if (n != 0 || x != 0)
        {
            int count = 0;
            for (int a = 1; a <= n; a++)
            {
                for (int b = 1; b <= n; b++)
                {
                    for (int c = 1; c <= n; c++)
                    {
                        if (a < b && b < c && a + b + c == x)
                        {
                            count=count + 1;
                        }
                    }
                }
            }

            printf("%d\n", count);
        }
    } while (n != 0 || x != 0);
    
    return 0;
}