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: Memory Limit Exceeded)

import scala.io.StdIn._

object Main {
  def main(args: Array[String]) {
    def combinationCount(input: String): Unit = {
      if(input != "0 0") {
        val Array(toNum, sumNum) = input.split(" ").map(_.toInt)
        val combinationSeq = Seq.range(1, toNum + 1).combinations(3)
        val combinationNum = (for (i <- combinationSeq if i.sum == sumNum) yield i).length
        println(combinationNum)
        combinationCount(readLine())
      }
    }

    combinationCount(readLine())
  }
}