text: #ifndef GRAPHS_ADJACENCY_H
  #define GRAPHS_ADJACENCY_H
  
  
  class Vertex;
  
  class Corner;
  
  class Adjacency {
  
  private:
  
      Corner *corner;
  
  public:
  
      Corner *getCorner();
  
      void setCorner(Corner *corner);
  };
  
  #endif