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 Kotlin (judge verdict: Memory Limit Exceeded)

fun main(args: Array<String>) {
    while (true) {
        var count = 0
        val (n, target) = readLine()?.split(" ")?.map { it.toInt() } ?: return
        if (n == 0 && target == 0) break
        val checker = hashSetOf<CustomTriple>()
        (1..n).forEach { i ->
            (2..n).forEach { j ->
                (3..n).forEach { k ->
                    if (i != j && j != k && k != i && i + j + k == target) {
                        var hasCombination = false
                        for (it in checker)  {
                            val tri = CustomTriple(i,j,k)
                            if (it.equals(tri)) {
                                hasCombination = true
                                continue
                            }
                        }
                        if (!hasCombination){
                            count++
                            checker.add(CustomTriple(i, j, k))
                        }
                    }
                }
            }
        }
        println(count)
    }
}

data class CustomTriple(val f: Int, val s: Int, val t:Int){

    override fun equals(other: Any?): Boolean {
        return other != null &&
                other is CustomTriple &&
                this.f in listOf(other.f, other.s, other.t) &&
                this.s in listOf(other.f, other.s, other.t) &&
                this.t in listOf(other.f, other.s, other.t)
    }

    override fun hashCode(): Int {
        return super.hashCode()
    }
}