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())

def f(a, b):
    sho, amari = int(a/b), a%b
    return sho, amari


def ans(l, m, s):
    cnt = 0

    R_s, R_a = f(N, l)

    for i in range(R_s + 1):
        x = R_a + i * l # R を i 個使う
        G_s, G_a = f(x, m)
        for j in range(G_s + 1):
            y = G_a + j * m # G を j 個使う
            if y % s == 0:
                cnt += 1
    return cnt

li = [R, G, B]
li.sort(reverse=True)

cnt = ans(li[0], li[1], li[2])

print(cnt)