#include <bits/stdc++.h>
using namespace std;

int main() {
	double n, sum = 0, u = 0;
	cin >> n;
	for (double i = 1;; i++) {
		sum += 1 / i;
		if (sum > n) {
			u = i;
			break;
		}
	}
	cout << u;
	return 0;
}