include/AD/tries/patricia.h

   1 //////////////////////////////////////////////////////////////////////////////
   2 // NOTICE:
   3 //
   4 // ADLib, Prop and their related set of tools and documentation are in the
   5 // public domain.   The author(s) of this software reserve no copyrights on
   6 // the source code and any code generated using the tools.  You are encouraged
   7 // to use ADLib and Prop to develop software, in both academic and commercial
   8 // settings, and are free to incorporate any part of ADLib and Prop into
   9 // your programs.
  10 //
  11 // Although you are under no obligation to do so, we strongly recommend that
  12 // you give away all software developed using our tools.
  13 //
  14 // We also ask that credit be given to us when ADLib and/or Prop are used in
  15 // your programs, and that this notice be preserved intact in all the source
  16 // code.
  17 //
  18 // This software is still under development and we welcome any suggestions
  19 // and help from the users.
  20 //
  21 // Allen Leung
  22 // 1994
  23 //////////////////////////////////////////////////////////////////////////////
  24
  25 #ifndef patricia_tries_h
  26 #define patricia_tries_h
  27
  28 //
  29 // Patricia (Practical Algorithm To Retrieve Information
  30 //    Coded In Alphanumeric) tries.
  31 //
  32
  33 class Patricia {
  34
  35    Patricia(const Patricia&);               // No initialization allowed
  36    Patricia& operator = (const Patricia&);  // No assignment allowed
  37
  38 protected:
  39
  40    typedef unsigned char Symbol;
  41
  42    struct Trie {
  43       unsigned char * keys;
  44       Trie ** children;
  45    };
  46
  47    typedef Trie * Node;
  48
  49    Node trie;
  50
  51 public:
  52
  53    Patricia();
  54   ~Patricia();
  55
  56    Node root() const                  { return trie; }
  57    Node child(Node n, Symbol c) const { return n->children[c]; }
  58 };
  59
  60 #endif