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: Wrong Answer)

import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in) ;

		int sum ;           //sum??????????????°???????¨???§???
		int N = 0 ;         //N ???????¨????x??¨??????????????????????????°??§???
		
		while(true) {
	//??\???????????????????????????
		int n = sc.nextInt();
		int x = sc.nextInt();
		if(n == 0 & x == 0) break;
	//???????¨???????????????????????????????	   
	        for(int i = 1; i <= (n-2) ; i++) {
			   for(int j = (i+1) ; j <=(n-1) ; j++) {
				  for(int k = (j+1) ; k <= n ; k++) {
					 sum = i+j+k ;
					 if(sum == x) {
						N ++ ;
					  }  
				  }
			   }
		    }
		  
		}

    	System.out.println(N);
	
		
		sc.close();
	}

}