#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cstdlib>
#include<vector>
#include<string>
#include<sstream>
#include<cmath>
#include<numeric>
#include<map>
#include<stack>
#include<queue>
#include<list>
using namespace std;
int inf = 1000000000;

int main(void) {

  long long int d;
  cin >> d;
  d *= 108;
  double a = d*1.0 / 100;
  printf("%.10lf\n", a);


  return 0;
}

// EOF