189A - Cut Ribbon

using namespace std;
int n;
int v[3];
int mem[4010];
bool vis[4010];
int dp(int remainder)
{
    if (remainder == 0)
        return 0;
    else if (remainder < 0)
        return INT_MIN;
    if (vis[remainder])
        return mem[remainder];
    int ans = INT_MIN;
    for (int i = 0; i < 3; ++i)
    {
        ans = max(ans, 1 + dp(remainder - v[i]));
    }
    vis[remainder] = true;
    mem[remainder] = ans;
    return ans;
}
int main(void)
{
    cin >> n >> v[0] >> v[1] >> v[2];
    cout << dp(n) << endl;
    return 0;
}