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