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

public class Main {

    public static void main(String[] args) throws IOException {


        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        while(true) {
            
            String[] line = br.readLine().split(" ");
            int n = Integer.parseInt(line[0]);
            int x = Integer.parseInt(line[1]);
            int num = 0;
            
            if(n == 0 && x == 0) { break; }
            
            for (int a = 1; a <= n; a++){
                for (int b = 2; b <= n; b++){
                    for(int c = 3; c <= n; c++){
                        if( a+b+c == x && a < b && b < c ) {
                            num += 1;
                        }
                    }
                }           
            }
            
            System.out.println(num);
            
        }
            
                
    }


}