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 5.4.1) (judge verdict: Time Limit Exceeded)

int main(void){
  int R, G, B, N;
  scanf("%d %d %d %d", &R, &G, &B, &N);

  int count = 0;
  int r, g, b;
  int r_max, b_max, g_max;
  
  r_max = N/R;
  for(r=0;r<=r_max;r++){
    b_max = (N-r*R)/B;
  	for(b=0;b<=b_max;b++){
      g_max = (N-r*R-b*B)/G;
      for(g=0;g<=g_max;g++){
        if(N - r*R - b*B - g*G == 0){
          count += 1;
        }
      }
    }
  }
  printf("%d", count);
}