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()
{
    int R, G, B, N;
    int count = 0;
    // 整数の入力
    scanf("%d", &R);
    scanf("%d", &G);
    scanf("%d", &B);
    scanf("%d", &N);

    for (int r = 0; r * R <= N; r++) {
        for (int g = 0; g * G <= (N - r * R); g++) {
            int n = N - (r * R) -  (g * G);
//    printf("%d %d %d\n", r, g, n);
            if ((n % B) == 0) count++;
        }
    }
    
    
    printf("%d\n", count);
/*
    // スペース区切りの整数の入力
    scanf("%d %d",&b,&c);
    // 文字列の入力
    scanf("%s",s);
    // 出力
    printf("%d %s\n",a+b+c,s);
*/
    return 0;
}