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>
#include <stdlib.h>

int main()
{
    int r, g, b, n;
    scanf("%d %d %d %d", &r, &g, &b, &n);
    int i, j, k, ans = 0;
    for (i = 0; i * r <= n; i++)
    {
        for (j = 0; j * g <= n; j++)
        {
            k = n - (i * r + j * g);
            if (k >= 0 && k % b == 0)
            {
                ans++;
            }
        }
    }
    printf("%d\n", ans);
    return 0;
}