text: #ifndef RULE_H_INCLUDED
  #define RULE_H_INCLUDED
  
  #include <vector>
  #include <string>
  
  class Rule {
  public:
    Rule();
    ~Rule();
    void set(int x1, int y1, int x2, int y2, int diff);
    void set(int x1, int y1, int x2, int y2, bool greater);
  
    bool check(std::vector<std::vector<int>> matrix) const;
    bool valid(int x, int y, int sx, int sy) const;
    std::string to_string() const;
    float xpos() const;
    float ypos() const;
    std::string rule() const;
  private:
    bool num;
    int diff;
    bool greater;
    int x1;
    int y1;
    int x2;
    int y2;
  };
  
  #endif //RULE_H_INCLUDED
  