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;

public class Main {
	public static void main(String[] args){
		//???????????????????????????
		int count =0;
		//????????£????????????
		Scanner sc =  new Scanner(System.in);
		while(true){
			//???????????°
			int n = sc.nextInt();
			//???????????????
			int  x = sc.nextInt();
			//??\???????????????????????±0?????£????????????
			if( n==0 && x ==0){
				break;
			}
			//??????????¶???????
			//???+???+??? //???+???+1+???+2 ??§?¨???? ???????????°????????????
			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 == x){
							count++;
						}
					}
				}
			}
			System.out.println(count);
			//????????????????????????
			count =0;
		}
	}
}