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: Time Limit Exceeded)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace app2
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] RGBN = Console.ReadLine().Split(' ');
            int R = int.Parse(RGBN[0]);
            int G = int.Parse(RGBN[1]);
            int B = int.Parse(RGBN[2]);
            int N = int.Parse(RGBN[3]);
            int count = 0;

            for (int i = 0; i <= 3000; i++)
            {
                for(int j = 0; i + j <= 3000; j++)
                {
                    for (int k = 0; i + j + k <= 3000; k++)
                    {
                        int sum = R * i + G * j + B * k;

                        if (N == sum)
                        {
                            count++;
                            //Console.WriteLine($"{i} {j} {k} {sum}");
                        }
                    }
                }
            }
            Console.WriteLine($"{count}");
        }
    }
}