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.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    while(true) {
      int count = 0;
      int n = sc.nextInt();
      int x = sc.nextInt();
      if(n == 0 && x == 0) {
        break;
      } else {
        for(int i = 1; i < n + 1; i++) {
          for(int j = 1; j < n + 1; j++) {
            int k = x - i - j;
            if(i != j && i != k && j != k && k < n + 1 && k > 0) {
              count++;
            }
          }
        }
        System.out.println(count / 6);
      }
    }
  }
}