#include<bits/stdc++.h>
using namespace std;
double x,peo=1300000000,cnt;
int main(){
    cin>>x;
    x=x/100;
    while(1){
        peo*=(1+x);
        cnt++;
        if(peo>=2000000000){
            cout<<cnt;
            return 0;
        }
    }
    return 0;
}