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 JAVA (judge verdict: Wrong Answer)

import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {
	public static void main(String[] args)throws Exception{
		InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        
        while (true)
        {
        	String[] nx = br.readLine().split(" ");
            int n = Integer.parseInt(nx[0]);
            int x = Integer.parseInt(nx[1]);
            if(n == 0 && x == 0)
            	break;
            
            int count = 0;
            for (int i = 1; i <= n - 2; i++)
            {
            	for (int j = i + 1; j <= n -1; j++)
            	{
            		for (int k = i + 2; k <= n; k++)
            		{
            			if ((i + j + k) == x)
            				count++;
            		}
            	}
            }
            System.out.println(count);
        }
        
		
	}

}