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.*;
import java.util.*;
public class Main{
	public static void main(String args[]) throws Exception{
		Scanner cin= new Scanner(System.in);
	while(true){
		int n= cin.nextInt();
		int x= cin.nextInt();
		int count= 0;
		
		if( n==0 && x==0 ){
			break;
		}
		else{
			int i,j,k;
			for(i=1;i<n-1;i++){
			for(j=i+1;j<n;j++){
			for(k=j+1;k<n+1;k++){
				if( i+j+k==x ){
					count++;
					break;
				}
			}
			}
			}
			System.out.println(count);
		}
	}
	}
}