text: #include "calculator.h"
  #include <iostream>
  #include <string>
  
  using namespace std;
  
  int main()
  {
      string rpn{"2 7 + 3 / 14 3 - 4 * + 2 /"};
      Calculator c(15.0);
      double result1 = c.Add(15).Divide(2).GetResult();
      double result2 = c.calculateRPN(rpn);
      cout << "The result of calculation is: " << result1 << endl;
      cout << "The result of RPN expression: \"" << rpn << "\" is: " <<   result2 << endl;
      return 0;
  }
  
  