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: Time Limit Exceeded)

stoi(s) = parse(Int, s)

function solve()
    R, G, B, N = map(stoi, split(chomp(readline())))

    ans = 0
    for r in 0:div(N, R), g in 0:div(N, G)
        b =  div(N - R*r - G*g, B)
        b < 0 && continue
        if R*r + G*g + B*b == N
            ans += 1
        end
    end

    println(ans)

    return nothing
end

solve()