#include <bits/stdc++.h>
#include <iostream>

using namespace std;

#define FOR(x,z,n) for(int x=z;x<n;x++)
#define mp make_pair
typedef long long ll;
typedef pair<int, int> iPair;

int main() {
	ll x;
	ll years = 1, temp = 100;
	cin >> x;
	while (true){
		temp *= 1.01;
		if (temp >= x) break;
		years++;
	}
	cout << years;
}