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 C++ (judge verdict: Time Limit Exceeded)

#include <iostream>
    using namespace std;
      
    int main() {
int n,x ;
while (1) {
    cin >> n >> x ;
    if (n == 0 && x == 0){
        break;
    };
int p;
p=0;
for (int h=1; h<=n-2; h++){
    for (int i=h+1; h<=n-1 ; i++){
        for (int j=i+1; j<=n; j++){
            if(h+i+j == x){
                p=p+1;
            }
        }
    }
}
cout<< p <<endl;
}
 
    return 0;
    }