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.collection.mutable.ListBuffer
import scala.io.StdIn

object Main extends App {

  var Array(n, x) = Array(-1, -1)
  var count = 0
  val buff = ListBuffer.empty[Int]
  
  while(n != 0 || x != 0){
    val Array(inn, inx) = StdIn.readLine().split(' ').map(_.toInt)
    n = inn
    x = inx
    count = 0
    (1 to n).foreach{ h =>
      (h+1 to n).foreach{ i =>
        (i+1 to n).foreach{ k =>
          count += (if(h + i + k == x) 1 else 0)
        }
      }
    }
    
    buff += count
  }
  
  buff.dropRight(1).foreach(println)
  
}