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)

import scala.io.Source

object Main extends App {
  val lines = Source.stdin.getLines.toList.init

  val count: List[List[String]] =
  for {
    line <- lines
  } yield { val Array(max, sum) = line.split(" ").map(_.toInt)
            val li = List.range(1, max+1)
            for {
              i <- li
              j <- li
              n <- li
              if (i+j+n == sum)
              if (i < j && j < n)
            } yield { s"$i + $j + $n" }
  }

  count.map(_.length).map(println)
}