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.IOException;
import java.util.Scanner;

class Main {

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

		Scanner scane = new Scanner(System.in);

		int n = 0, x = 0;

		n = scane.nextInt();
		x = scane.nextInt();

		int count =0;


		while ((n+x) != 0) {

			count =0;

			for(int i= n; i>0; --i ){
				for(int j = i-1; j>0; --j){
					for(int t =j-1; t>0; --t){

						if((i+j+t) == x){
							count++;
						}

					}
				}
			}

			System.out.println(count);



			n = scane.nextInt();
			x = scane.nextInt();

		}



	}
}