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: Wrong Answer)

using System;
using System.Linq;

namespace Test
{
    class MainClass
    {
        public static void Main(string[] args)
        {
            while (true)
            {
                var inputs = Console.ReadLine().Split(' ');
                var n = int.Parse(inputs[0]);
                var x = int.Parse(inputs[1]);
                if ((n == 0) && (x == 0)) return;
                var combination = 0;

                for (int i = 0; i < n; i++)
                {
                    for (int j = 0; j < n; j++)
                    {
                        for (int k = 0; k < n; k++)
                        {
                            if ((i + j + k) == x) combination++;
                        }
                    }
                }
                Console.WriteLine(combination / n);
            }
        }
    }
}