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 scan = new Scanner(System.in);
        while (true) {
            int n = scan.nextInt();
            int x = scan.nextInt();

            if(n==0 && x==0) break;
            int count=0;
            for(int i=1; i<n; ++i){
                for(int j=i; j<n; ++j){
                    if(i==j) {
                        continue;
                    }
                    int num = x - (i+j);
                    if(num<1) {
                        break;
                    }
                    if(num<j) {
                        break;
                    }
                    if(i != num && j != num && num <= n) {
                        count++;
                    }
                    num = 0;
                }
            }
            System.out.println(count);}
    }
}