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: Time Limit Exceeded)

#include <iostream>

using namespace std;

int main(void){
  int R, G, B, N, cnt=0;
  scanf("%d %d %d %d", &R, &G, &B, &N);
  for(int i=0; i<=3000/R; ++i){
    for(int j=0; j<=3000-R*i; ++j){
      for(int k=0; k<=3000-R*i-G*j; ++k){
        if(R*i + G*j + B*k == N)
          cnt++;
      }
    }
  }
  printf("%d\n", cnt);
  return 0;
}