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 Java8 (OpenJDK 1.8.0) (judge verdict: Time Limit Exceeded)

import java.util.ArrayList;
import java.util.Scanner;

class Main {
	static int R,G,B,N;
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		R = sc.nextInt();
		G = sc.nextInt();
		B = sc.nextInt();
		N = sc.nextInt();

		ArrayList<Integer> rlist = new ArrayList<>();
		ArrayList<Integer> glist = new ArrayList<>();
		ArrayList<Integer> blist = new ArrayList<>();

		rlist.add(0);
		for (int i = R; i <= N; ) {
			rlist.add(i);
			i += R;
		}
		glist.add(0);
		for (int i = G; i <= N; ) {
			glist.add(i);
			i += G;
		}
		blist.add(0);
		for (int i = B; i <= N; ) {
			blist.add(i);
			i += B;
		}

		//check(blist);

		int count = 0;

		for (int i = 0; i < rlist.size(); i++) {
			for (int j = 0; j < glist.size(); j++) {
				for (int k = 0; k < blist.size(); k++) {
					int tmp = rlist.get(i) + glist.get(j) + blist.get(k);
					if (tmp == N) {
						count++;
					}
				}
			}
		}
		System.out.println(count);
	}

	static void check(ArrayList list) {
		for (int i = 0; i < list.size(); i++) {
			System.out.println(list.get(i));
		}
	}
}