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: Accepted)

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        solve();
    }

    private static void solve() {
        Scanner input = new Scanner(System.in);

        int r = input.nextInt();
        int g = input.nextInt();
        int b = input.nextInt();
        int n = input.nextInt();

        int ansCnt = 0;

        for (int rn = 0; rn <= n/r; rn++) {
        	if (rn * r == n) {
        		ansCnt++;
        	} else {
            	for (int gn = 0; gn <= n/g; gn++) {
            		if (rn * r + gn * g == n) {
            			ansCnt++;
            		} else {
            			int rem = n - (rn * r + gn * g);
            			if (rem > 0) {
            				if (rem % b == 0) {
                    			ansCnt++;
            				}
            			}
            		}
            	}
        	}
        }

        System.out.println(ansCnt);
    }
}