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)

object Main extends App {
  val in = scala.io.Source.stdin.getLines.toSeq
  val ls = in.head.split(' ').map(_.toInt)
  val R = ls(0)
  val G = ls(1)
  val B = ls(2)
  val N = ls(3)
  val s = Seq(R,G,B).sorted.reverse
  //println(s)
  val r = s(0)
  val g = s(1)
  val b = s(2)
  var ret = 0
  (0 to N by r).map{ i =>
    (0 to N by g).map{ j =>
      if((N - i - j)>=0 && (N - i - j) % b == 0){
        //println(i, j, (N-i-j)/b )
        ret += 1
      }
    }
  }
  println(ret)
}