#include <bits/stdc++.h>
using namespace std;
const long long MOD = 1000000007;
const long long INF = 9999999999999999;
using ll = long long;
int main(){
  ll X;
  ll ans = 0;
  ll p = 100;
  while(1){
    p *= 1.01;
    ans++;
    if(p>= X){
      break;
    }
  }
  cout << ans << endl;
  return 0;
}