text: #include <iostream>
  #include <iomanip>
  #include <cmath>
  
  using namespace std;
  
  int main()
  {
      double x;
      cin >> x;
      if(x <= -1)
          cout << setiosflags(ios::fixed) << setprecision(2) << x + 1 << endl;
      else if(x >= 1)
          cout << setiosflags(ios::fixed) << setprecision(2) << log10(x) << endl;
      else if(x > -1 && x < 1)
          cout << setiosflags(ios::fixed) << setprecision(2) << abs(x) << endl;
  
      return 0;
  }