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: Accepted)

#include <stdio.h>

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