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 scan = new Scanner(System.in);
		int sum, count = 0;
		int n, x;
		boolean flg = true;
		
		while(true) {
			n = scan.nextInt();
			x = scan.nextInt();
			
			if(n == 0 && x == 0)break;
			
			count = 0;
			
			for(int i = 1; i <= n; i++) {
				sum = i;
				for(int j = 1 + i; j <= n; j++) {
					sum = i;
					if( j != i) {
						sum += j;
						flg = true;
					}else {
						flg = false;
					}
					for(int k = 1 + j; k <= n; k++) {
						if( flg == true) {
							sum = i + j;
							if( i != j && i != k && j != k) {
								sum += k;
								
								if( x == sum) {
									count++;
								}
							}
						}
						
						
					}
				}
			}
			
			System.out.println(count);
			
		}
		
	}
}