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.*;

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