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);
int[] A=new int[101];
int a=0;
while(true){
String x=scan.next();
String y=scan.next();
int n=Integer.parseInt(x);
int m=Integer.parseInt(y);
if(n==0&&m==0)
break;
int sum=0;
for(int i=1;i<=n;i++){
for(int j=i+1;j<=n;j++){
for(int k=j+1;k<=n;k++){
if(i+j+k==m)
sum++;
}
}
}
A[a]=sum;
a++;
}
for(int z=0;z<a;z++)
System.out.println(A[z]);
}
}