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;

class A
{
    static void Main(string[] args)
    {
        while (true)
        {
            string hsda = Console.ReadLine();
            if (hsda == null) { break; }
            int ans = 0;
            //int a = int.Parse(hsda);
            int[] s = Console.ReadLine().Split().Select(int.Parse).ToArray();
            /*int[] s = new int[a + 1];

            if (a > 18) { a = 36 - a; }
            //   if (a == 1) { ans = 4; }else if (a == 0) { ans = 1; }
            if (a >= 1) { s[1] = 4; }
            s[0] = 1;
            if (a >= 2)
            {
                for (int i = 2; i <= a; i++)
                { s[i] = s[i - 2] + (i + 1) * (i + 1); }
            }
            Console.WriteLine(s[a]);
            //Console.ReadLine();
            */
            for(int i = 0+1; i < s[0]+1; i++) { for (int k = 0+1; k < s[0]+1; k++) {{ for (int m = 0+1; m < s[0]+1; m++) { for (int i1 = 0+1; i1 < s[0]+1; i1++) { if (i1!=k&&i1!=m&&i1!=k&&k!=m&&k!=i&&m!=i&&i + k + m + i1 == s[1]) { ans++; } }} } } }
            Console.WriteLine(ans);
        }
    }
}