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.InputStreamReader;
import java.io.IOException;
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 sun = 0;
			if( n == 0 && x == 0) break;
			for(int i = 1; i <= n ; i++){
				for(int j = 1; j <=i ; j++){
					for(int k = 1; k <=j ; k++){
						if( i+j+k == x && i != j && i != k && j != k ){
							sun++;
						}
					}
				}
			}
			System.out.println(sun);
		}
	}
}