text: #ifndef __CALCULATOR_H__
  #define __CALCULATOR_H__
  
  class Calculator {
      public:
      int add(int first, int second);
      int sub(int first, int second);
      int divide(int first, int second);
      int multiply(int first, int second);
      int notCoverFuntion(int first, int second);
  };
  
  #endif //__CALCULATOR_H__
  