text: #include <iomanip>
  #include <iostream>
  
  #include "geometry.hpp"
  
  using std::cin;
  using std::cout;
  using std::endl;
  
  int main() {
      Vector2 a, b, c;
      cin >> a >> b >> c;
  
      double p = turning(a, b, c);
      if (is_same(p, 0.0))
          cout << "Go straight." << endl;
      else if (p < 0)
          cout << "Turn right." << endl;
      else
          cout << "Turn left." << endl;
  
      return 0;
  }  // function main
  