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 Python (3.4.3) (judge verdict: Accepted)

R, G, B, N = map(int, input().split())
counter = 0
if R < G:
  R, G = G, R
if G < B:
  G, B = B, G
if R < G:
  R, G = G, R
r = 0
while r * R <= N:
  g = 0
  if B == 1:
    counter += (N - r*R)//G + 1
    r += 1
    continue
  while g * G <= N:
    b = (N - r*R - g*G)/B 
    if b < 0:
      break
    elif b == int(b):
      counter += 1
    g += 1
  r += 1
print(counter)