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++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>
#include <string>
#include <iomanip>
#include <algorithm>
#include <vector>
#include <cmath>
#include <queue>
#define lli long long int
#define rep(i,n) for(int i=0; i<n; i++)
#define loop(i, j, n) for(int i=j; i<n; i++)
using namespace std;
using Graph = vector<vector<int>>;
int main()
{
	int r, g, n, cnt=0;
	double b, z;
	cin >> r >> g >> b >> n;

	rep(x,3001){
		rep(y,3001){
			z = (n-r*x-g*y)/b;
			if(z == (int)z && (z >= 0 && z <= 3000)){
				cnt++;
			}
		}
	}
	cout << cnt <<endl;
	return 0;
}