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.io.*;
import java.util.Arrays;
class Main{
    public static void main(String[] args) throws IOException {
        int i,j,k,cnt;
        int[] n = new int[990];
        String[] str = new String[990];
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        for(;;){
            str = in.readLine().split(" ");
            for(i=0;i<2;i++){
                n[i]=Integer.parseInt(str[i]);   
            } 
            cnt=0;
            if(n[0]==0 && n[1]==0) break; 
            for(i=1;i<=n[0];i++){
                for(j=i+1;j<=n[0];j++){
                    for(k=j+1;k<=n[0];k++){
                        cnt+=(i+j+k==n[1] ? 1 : 0);
                    }
                } 
            }
            System.out.println(cnt);
        }
        System.out.flush();
    }
}