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)

#include <stdio.h>

int main(void){
    int a;
    a = 0;
    int b;
    b = 0;
    int c;
    c = 0;
    int d;
    d = 0;
    int sum;
    sum = 0;
    int check;
    check = 0;

    scanf("%d %d %d %d", &a, &b, &c, &d);
    
    for (int i = 0; i <= a; a++){
        for (int j = 0; i <= b; b++){
            for (int k = 0; i <= c; c++){
                sum = a * i + b * j + c * k;
                if(sum == d){
                    check++;
                }
            }
        }
    }

    printf("%d", check);

    return 0;
}