#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <utility>
#include <cmath>

using namespace std;

int main() {
	int hp, attack, critical;

	cin >> hp >> attack >> critical;

	double ans = 1e9;
	for (int i = ceil(1.0 * hp / critical); i >= 0; i--) {
		int j = max(0, (int) ceil(1.0 * (hp - critical * i) / attack));
		ans = min(ans, 1.5 * i + j);
	}

	cout << ans << endl;
	return 0;
}