#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (n); i++)
using ll = long long;
using vll = vector<ll>;
using vi = vector<int>;
using vvi = vector<vector<int>>;
using vvll = vector<vector<ll>>;
const ll inf = 1e16;
const ll md = 1000000007;

int main() {
  double n;
  cin>>n;
  int c=1e4;
  double nog=(c-n)/100;
  double gul=n*99/100;
  cout<<nog*100/(nog+gul)<<endl;
  return 0;
}