
// Problem : B - 1%
// Contest : AtCoder - AtCoder Beginner Contest 165
// URL : https://atcoder.jp/contests/abc165/tasks/abc165_b
// Memory Limit : 1024 MB
// Time Limit : 2000 ms
// Powered by CP Editor (https://github.com/cpeditor/cpeditor)

#include <bits/stdc++.h>

#define FIO ios_base::sync_with_stdio(0); cin.tie(0);
#define T() int tt; cin >> tt; rep1(qq,1,tt)
#define rep(i,start,lim) for(int i=start;i<lim;i++)
#define rep1(i,start,lim) for(int i=start; i<=lim; ++i)
#define repd(i,start,lim) for(int i=start;i>=lim;i--)
#define mp make_pair
#define pb push_back
#define ff first
#define ss second
#define br cout<<"\n"
#define MOD (1000000007LL)
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()
#define eps (1e-6)
#define what_is(x) cerr << #x << " is " << x << "\n";
#define int long long int
#define infll 9e18
#define inf 1e12

#define lnode (2 * node + 1)
#define rnode (2 * node + 2)

using namespace std;

typedef pair<int, int> pii;

const int N = 3 * 1e6 + 2;

int n, k;

int32_t main(){

  FIO
  cout << fixed << setprecision(18);
  //freopen("input.txt", "r", stdin);
  //freopen("output.txt", "w", stdout);

  long double p = 100.0;
  long double m = 1.01;
  int x; cin >> x;
  for(int i = 1; ; ++i){
    int t = i;
    long double val = p;
    while(t--){
      val *= m;
      val = floor(val);
    }
    if((int)val >= x){
      cout << i << '\n';
      break;
    }
  }


	return 0;
}




