#include <bits/stdc++.h>
using namespace std;
int dp[4003];
int main() {
	int n, a, b, c;
	cin >> n >> a >> b >> c;
	memset(dp, 0xcf, sizeof(dp));
	dp[0] = 0;
	for (int i = 1; i <= n; i++) {
		if (i >= a) {
			dp[i] = max(dp[i], dp[i - a] + 1);
		}
		if (i >= b) {
			dp[i] = max(dp[i], dp[i - b] + 1);
		}
		if (i >= c) {
			dp[i] = max(dp[i], dp[i - c] + 1);
		}
	}
	cout << dp[n];
	return 0;
}