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.util.Scanner;

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

        String[] inputs = scan.nextLine().split(" ");
        int n = Integer.parseInt(inputs[0]);
        int x = Integer.parseInt(inputs[1]);
        int num = 0;
        int k;

        for (int i=1; i<n-1; i++){
            for (int j=i+1; j<n; j++){
                //for (int k=j+1; k<n+1; k++){
                //    if (i+j+k == x)
                //        num += 1;
                //        break;
                
                //?????????????¶?????????¶??? i+j+k <= x
                //???????????? k <= x-i-j

                k = x-i-j;
                if (k > j && k <= n)
                    num += 1;
            }
        }
        if (num != 0){
            System.out.println(num);
        }
    }
}