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.util.Scanner;
public class Main {
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		
		int n=sc.nextInt();
		int x=sc.nextInt();
		int p1,p2,p3;
		int cnt=0;
		while(n!=0 || x!=0){
			for(p1=1;p1<=n;p1++){
				for(p2=(p1+1);p2<=n;p2++){
					if(((p1+p2)>=x) ||(p1==p2)) break;
					for(p3=(p2+1);p3<=n;p3++){
						if(((p1+p2+p3)>x)||(p2==p3)){
							break;
						}else if((p1+p2+p3)==x){
							cnt++;
						}
					}//for	
				}//for
			}//for
			System.out.println(cnt);
			cnt=0;
			n=sc.nextInt();
			x=sc.nextInt();
		}//while
	}
}