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 C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main(string[] args)
    {
        string[] input = Console.ReadLine().Split(' ');
        int R = int.Parse(input[0]);
        int G = int.Parse(input[1]);
        int B = int.Parse(input[2]);
        int N = int.Parse(input[3]);
        int counter = 0;
        for(int i = 0;i < 3000/R; i++)
        {
            int num=N-R*i;
            for (int j = 0; 0 <= N-R*i-G*j; j++)
            {
                for (int k = 0; 0<= N - R * i - G * j-B*k; k++)
                {
                    int sum = N-R*i-G*j-B * k;
                    if (sum == 0) { counter++;
                    }
                }
            }
        }
        Console.WriteLine(counter);
    }
}