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: Accepted)

import java.util.Scanner;

public class Main {
    public static void main(String[] args){
        Scanner scanner = new Scanner(System.in);

        int n, x;
        int count = 0;
        while(true){
            n = scanner.nextInt();
            x = scanner.nextInt();
            if(n == 0 && x == 0){
                break;
            }
            count = 0;
            for(int a = n; a > 0; a--){
                for(int b = n; b > 0; b--){
                    for(int c = n; c > 0; c--){
                        if(x == (a+b+c) && a != b && b != c && c != a){
                            count++;
                        }
                    }
                }
            }
            System.out.println(count/6);
        }


        scanner.close();
    }
}