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>
#include <stdint.h>
#include <inttypes.h>

int main (int argc, char const *argv[])
{
    int64_t R, G, B, N;
    int64_t ans = 0;

    scanf("%"PRId64"%"PRId64"%"PRId64"%"PRId64, &R, &G, &B, &N);

    for (int r = 0; r <= (N / R); r++) {
        for (int g = 0; g <= ((N - R * r) / G); g++) {
            if (((N - R * r - G * g) % B) != 0) continue;
            ans++;
        }
    }

    printf("%"PRId64"\n", ans);
}