Problem:
Score : 200 points

Problem Statement

Snuke has come to a store that sells boxes containing balls. The store sells the following three kinds of boxes:

Red boxes, each containing R red balls

Green boxes, each containing G green balls

Blue boxes, each containing B blue balls

Snuke wants to get a total of exactly N balls by buying r red boxes, g green boxes and b blue boxes.
How many triples of non-negative integers (r,g,b) achieve this?

Constraints

All values in input are integers.

1 \leq R,G,B,N \leq 3000

Input

Input is given from Standard Input in the following format:

R G B N

Output

Print the answer.

Sample Input 1

1 2 3 4

Sample Output 1

4

Four triples achieve the objective, as follows:

(4,0,0)

(2,1,0)

(1,0,1)

(0,2,0)

Sample Input 2

13 1 4 3000

Sample Output 2

87058

Solution in Scala (2.11.7) (judge verdict: Accepted)

import scala.io.{StdIn => in}

object Main extends App {
  val Array(r, g, b, n) = in.readLine.split(" ").map(_.toInt)

  var cnt = 0
  for {
    i <- 0 to n/r
    j <- 0 to n/g
    k = n - r*i - g*j
    if 0 <= k
  } {
    if(k == 0 && r*i + g*j == n) {
      cnt += 1
      debug(i,j,k)
    }
    else if(k%b == 0 && (r*i + g*j + k) == n) {
      cnt += 1
      debug(i,j,k)
    }
  }

  val ans = cnt
  println(ans)

  def debug(any:Any*):Unit = {
    if(this.getClass.toString != "class Main$")
      println(any.mkString(" "))
  }
}