#include<bits/stdc++.h>
using namespace std;
using i64 = int_fast64_t;
#define rep(i, N) for(i64 i = 0; i < N; i++)
#define Rep(i, k, N) for(i64 i = k; i < N; i++)
#define all(v) v.begin(), v.end()
#define eb emplace_back
#define Cout(s) cout << s << endl
string Yes(bool b) {if(b){return "Yes";} else {return "No";}}
string YES(bool b) {if(b){return "YES";} else {return "NO";}}

int main(){
    i64 X;
    cin >> X;
    i64 n = 100ll;
    
    int i = 0;
    while(n < X){
        n = n * (101.0 / 100.0);
        i++;
    }

    cout << i << endl;
}
