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: Wrong Answer)

import java.util.*;

class Main {
	public static void main (String[] args) {
		Scanner scan = new Scanner(System.in);
		while(true) {
			int n = scan.nextInt();
			int x = scan.nextInt();
			if(n == 0 && x == 0) break;
			System.out.println(search(n , x));
		}

	}

	static int search(int n , int x) {
		int c = 0;
		int k = n - 3 > x ? x - 3 : n ;
		int m = 2;
		while(true) {
			c += m / 2;
			m++;
			k--;
			if(m >= k ) break;
		}
		return c;
	}
}