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 (Clang 3.8.0) (judge verdict: Accepted)

#include<stdio.h>
int main(void){
  int r,g,b,n,cnt = 0;
  scanf("%d %d %d %d",&r,&g,&b,&n);
  for(int i = 0;i <= n / r;i++){
    for(int j = 0;j <= n / g;j++){
      int k = n - i * r - j * g;
      if(k > -1 && k % b < 1){
        cnt++;
      }
    }
  }
  printf("%d\n",cnt);
  return 0;
}