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;
import java.util.StringTokenizer;

public class Main {

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		while(true) {
			StringTokenizer st=new StringTokenizer(br.readLine());
			int n=Integer.parseInt(st.nextToken());
			int x=Integer.parseInt(st.nextToken());

			if(n==0 && x==0) {
				break;
			}

			int count=0;
			for(int a=1;a<=n;a++){
				for(int b=1;b<=n;b++) {
					for(int c=0;c<=n;c++) {
						if(a+b+c==x && a<b && b<c) {
							count++;
						}
					}
				}
			}
			System.out.println(count);
		}
	}
}