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++ (GCC 9.2.1) (judge verdict: Wrong Answer)

#include<bits/stdc++.h>

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define ll long long

#pragma GCC optimize("Ofast")



using namespace std;

bool is_integer( float x ){
    return floor(x) == x;
}
bool is_integer(double x){
    return floor(x) == x;
}


int main() {

    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    float a[3]; cin >> a[0] >> a[1] >> a[2];
    float n; cin >> n;
    int ans = 0;
    sort(a,a+3);

    rep(i,3001){
        rep(j,3001){
            if(is_integer((n-i*a[0]-j*a[1])/a[2]) && (n-i*a[0]-j*a[1]) >= 0){
                ans ++;
            }
        }
    }

    cout << ans;

    return 0;
}