include/AD/strings/kmp.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 Knuth_Morris_Pratt_string_matching_h
  26 #define Knuth_Morris_Pratt_string_matching_h
  27
  28 //
  29 //  String matching with the Knuth-Morris-Pratt algorithm\cite{KMP}
  30 //
  31
  32 #include <AD/strings/strmatch.h>
  33
  34 class KMP : public StringMatcher {
  35
  36    KMP(const KMP&);               // No copy constructor
  37    KMP& operator = (const KMP&);  // No assignment
  38
  39 protected:
  40
  41    typedef unsigned char Skip[256];
  42    Skip * skip;
  43    int patternLength;
  44
  45 public:
  46
  47    KMP() : skip(0) {}
  48    KMP(const char * pattern) : skip(0) { *this = pattern; }
  49   ~KMP() { delete [] skip; }
  50
  51    // Set new pattern
  52    void compile(const char * pattern, int length = -1);
  53    void operator = (const char * pattern) { compile(pattern); }
  54
  55    //  Returns position in pattern is a substring of text
  56    //  Returns -1 otherwise
  57    int Match(const char * text, int length = -1) const;
  58 };
  59
  60 #endif