Persistent Dictionaries Example

The following program shows how p_dictionary can be used. The operations insert(), delete(), del_item(), and change_inf() return a dictionary that can be used to save a certain "state" of the original.

#include <LEDA/core/p_dictionary.h>
#include <LEDA/core/string.h>

using namespace leda;

int main()
{
  p_dictionary<string, int> PD;
    //objects of type int, keys of type string
	
  p_dictionary<string,int> PD_backup1, PD_backup2;
    //used to store intermediate "states" of PD
 
  PD.insert("alpha",1);
  PD.insert("beta",2);

  PD_backup1=PD.insert("gamma",3);
     //store p_dictionary after insertion of <"gamma",3>

  PD.insert("delta",4);
  
  PD_backup2=PD.del("beta");
     //store p_dictionary after deletion of <"beta",2>

  PD_backup2=PD.insert("psi",10);
    //copies of PD can be changed independently
  
  PD.insert("epsilon",5);
  
  if (PD.locate("beta")) std::cout << "beta is contained in PD\n";
  else std::cout << "beta is not contained in PD\n";

  if (PD_backup1.locate("beta")) 
    std::cout << "beta is contained in PD_backup1\n";
  else std::cout << "beta is not contained in PD_backup1\n";

  if (PD_backup2.locate("beta")) 
    std::cout << "beta is contained in PD_backup2\n";
  else std::cout << "beta is not contained in PD_backup2\n";

  return 0;
}	  

See also:

Persistent Dictionaries

Dictionaries.

Partially Persistent Dictionary

Manual Entries:

Manual Page Persistent Dictionaries

User Defined Parameter Types

LEDA Item Concept

Linear Orders