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# (.NET Core 3.1.201) (judge verdict: Time Limit Exceeded)

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


class Program
{
    static void Main(string[] args)
    {
        // 入力
        //var s = Console.ReadLine();
        //var n = int.Parse(Console.ReadLine());
        int[] RGBN = Console.ReadLine().Split().Select(int.Parse).ToArray();
        var R = RGBN[0];
        var G = RGBN[1];
        var B = RGBN[2];
        var N = RGBN[3];
        var ans = 0;

        for (int r = 0; r <= N ; r++)
        {
            for (int g = 0; g <= N ; g++)
            {
                for (int b = 0; b <= N ; b++)
                {
                    if(R * r + G * g + B * b == N) ans ++;
                    else if (R * r + G * g + B * b > N) break;
                }
            }
        }


        // 出力
        Console.WriteLine(ans);
    }
}