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 Julia (0.5.0) (judge verdict: Accepted)

function main()
  RR,GG,BB,N=map(x->parse(Int,x),split(readline()))
  num=[RR,GG,BB]
  R=maximum(num)
  B=minimum(num)
  G=RR+GG+BB-R-B
  ans=0
  if R==G && G==B && N%R==0
    temp=N/R
    ans=Int(floor((temp+1)*(temp+2)/2))
  elseif R==G || G==B
    for rr=N:-R:0
      if rr%B==0
        ans+=Int(rr/B)+1
      end
    end
  else
    for rr=N:-R:0,rg=rr:-G:0
      ans+=rg%B==0
    end
  end
  println(ans)
end
main()