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 Ruby (2.3.3) (judge verdict: Runtime Error)

r, g, b, n = gets.chomp.split.map(&:to_i)
r, g, b, n = gets.chomp.split.map(&:to_i)
# 小さい順に並ぶ
boxes = [r, g, b].sort
answer = 0
for i in 0..n/boxes[2] do
  tmp2 = n - boxes[2] * i
  break if tmp2 < 0
  for j in 0..n/boxes[1] do
    tmp1 = tmp2 - boxes[1] * j
    break if tmp1 < 0
    for k in 0..n/boxes[0] do
      tmp0 = tmp1 - boxes[0] * k
      break if tmp0 < 0
      if tmp0 == 0
        answer += 1
      end
    end
  end
end

print("#{answer}\n")