// This may look like C code, but it is really -*- C++ -*- /* Copyright (C) 1988 Free Software Foundation written by Doug Lea (dl@rocky.oswego.edu) This file is part of GNU CC. GNU CC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY. No author or distributor accepts responsibility to anyone for the consequences of using it or for whether it serves any particular purpose or works at all, unless he says so in writing. Refer to the GNU CC General Public License for full details. Everyone is granted permission to copy, modify and redistribute GNU CC, but only under the conditions described in the GNU CC General Public License. A copy of this license is supposed to have been given to you along with GNU CC so you can know your rights and responsibilities. It should be in a file named COPYING. Among other things, the copyright notice and this notice must be preserved on all copies. */ #ifndef _PQ_h #ifdef __GNUG__ #pragma once #pragma interface #endif #define _PQ_h 1 #include #include ".defs.h" class PQ { protected: int count; public: int length(); // current number of items int empty(); virtual Pix enq( item) = 0; // add item; return Pix virtual deq(); // return & remove min virtual & front() = 0; // access min item virtual void del_front() = 0; // delete min item virtual int contains( item); // is item in PQ? virtual void clear(); // delete all items virtual Pix first() = 0; // Pix of first item or 0 virtual void next(Pix& i) = 0; // advance to next or 0 virtual & operator () (Pix i) = 0; // access item at i virtual void del(Pix i) = 0; // delete item at i virtual int owns(Pix i); // is i a valid Pix ? virtual Pix seek( item); // Pix of item void error(const char* msg); virtual int OK() = 0; // rep invariant }; #if defined(__OPTIMIZE__) || defined(USE_LIBGXX_INLINES) inline int PQ::length() { return count; } inline int PQ::empty() { return count == 0; } #endif #endif