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 Scala (judge verdict: Accepted)

object Main {

    def main(args: Array[String]): Unit = {
        val sc = new java.util.Scanner(System.in)

        combination(sc)
    }

    def combination(scanner: java.util.Scanner): Unit = {
        val n, x = scanner.nextInt
        var count = 0

        if( n != 0 || x != 0 ) {
            for( i <- 1 to n-2 ) {
                for( j <- i+1 to n-1 ) {
                    if( i < j && j < x-i-j && x-i-j <= n ) count += 1
                }
            }

            println(count)
            combination(scanner)
        }
    }
}