diff -r 2d6c8075d9d0 -r 818510fa3d99 src/lemon/bin_heap.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lemon/bin_heap.h	Wed Sep 29 15:30:04 2004 +0000
@@ -0,0 +1,203 @@
+/* -*- C++ -*-
+ * src/lemon/bin_heap.h - Part of LEMON, a generic C++ optimization library
+ *
+ * Copyright (C) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
+ * (Egervary Combinatorial Optimization Research Group, EGRES).
+ *
+ * Permission to use, modify and distribute this software is granted
+ * provided that this copyright notice appears in all copies. For
+ * precise terms see the accompanying LICENSE file.
+ *
+ * This software is provided "AS IS" with no warranty of any kind,
+ * express or implied, and with no claim as to its suitability for any
+ * purpose.
+ *
+ */
+
+#ifndef LEMON_BIN_HEAP_H
+#define LEMON_BIN_HEAP_H
+
+///\ingroup auxdat
+///\file
+///\brief Binary Heap implementation.
+///\todo It should be documented.
+
+#include <vector>
+#include <utility>
+#include <functional>
+
+namespace lemon {
+
+  /// \addtogroup auxdat
+  /// @{
+
+   /// A Binary Heap implementation.
+  template <typename Item, typename Prio, typename ItemIntMap,
+	    typename Compare = std::less<Prio> >
+  class BinHeap {
+
+  public:
+    typedef Item                             ItemType;
+    // FIXME: stl-ben nem ezt hivjak value_type -nak, hanem a kovetkezot...
+    typedef Prio                             PrioType;
+    typedef std::pair<ItemType,PrioType>     PairType;
+    typedef ItemIntMap                       ItemIntMapType;
+    typedef Compare                          PrioCompare;
+
+    /**
+     * Each Item element have a state associated to it. It may be "in heap",
+     * "pre heap" or "post heap". The later two are indifferent from the
+     * heap's point of view, but may be useful to the user.
+     *
+     * The ItemIntMap _should_ be initialized in such way, that it maps
+     * PRE_HEAP (-1) to any element to be put in the heap...
+     */
+    ///\todo it is used nowhere
+    ///
+    enum state_enum {
+      IN_HEAP = 0,
+      PRE_HEAP = -1,
+      POST_HEAP = -2
+    };
+
+  private:
+    std::vector<PairType> data;
+    Compare comp;
+    // FIXME: jo ez igy???
+    ItemIntMap &iim;
+
+  public:
+    BinHeap(ItemIntMap &_iim) : iim(_iim) {}
+    BinHeap(ItemIntMap &_iim, const Compare &_comp) : comp(_comp), iim(_iim) {}
+
+
+    int size() const { return data.size(); }
+    bool empty() const { return data.empty(); }
+
+  private:
+    static int parent(int i) { return (i-1)/2; }
+    static int second_child(int i) { return 2*i+2; }
+    bool less(const PairType &p1, const PairType &p2) const {
+      return comp(p1.second, p2.second);
+    }
+
+    int bubble_up(int hole, PairType p);
+    int bubble_down(int hole, PairType p, int length);
+
+    void move(const PairType &p, int i) {
+      data[i] = p;
+      iim.set(p.first, i);
+    }
+
+    void rmidx(int h) {
+      int n = data.size()-1;
+      if( h>=0 && h<=n ) {
+	iim.set(data[h].first, POST_HEAP);
+	if ( h<n ) {
+	  bubble_down(h, data[n], n);
+	}
+	data.pop_back();
+      }
+    }
+
+  public:
+    void push(const PairType &p) {
+      int n = data.size();
+      data.resize(n+1);
+      bubble_up(n, p);
+    }
+    void push(const Item &i, const Prio &p) { push(PairType(i,p)); }
+
+    Item top() const {
+      return data[0].first;
+    }
+    /// Returns the prio of the top element of the heap.
+    Prio prio() const {
+      return data[0].second;
+    }
+
+    void pop() {
+      rmidx(0);
+    }
+
+    void erase(const Item &i) {
+      rmidx(iim[i]);
+    }
+
+    Prio operator[](const Item &i) const {
+      int idx = iim[i];
+      return data[idx].second;
+    }
+
+    void set(const Item &i, const Prio &p) {
+      int idx = iim[i];
+      if( idx < 0 ) {
+	push(i,p);
+      }
+      else if( comp(p, data[idx].second) ) {
+	bubble_up(idx, PairType(i,p));
+      }
+      else {
+	bubble_down(idx, PairType(i,p), data.size());
+      }
+    }
+
+    void decrease(const Item &i, const Prio &p) {
+      int idx = iim[i];
+      bubble_up(idx, PairType(i,p));
+    }
+    void increase(const Item &i, const Prio &p) {
+      int idx = iim[i];
+      bubble_down(idx, PairType(i,p), data.size());
+    }
+
+    state_enum state(const Item &i) const {
+      int s = iim[i];
+      if( s>=0 )
+	s=0;
+      return state_enum(s);
+    }
+
+  }; // class BinHeap
+
+  
+  template <typename K, typename V, typename M, typename C>
+  int BinHeap<K,V,M,C>::bubble_up(int hole, PairType p) {
+    int par = parent(hole);
+    while( hole>0 && less(p,data[par]) ) {
+      move(data[par],hole);
+      hole = par;
+      par = parent(hole);
+    }
+    move(p, hole);
+    return hole;
+  }
+
+  template <typename K, typename V, typename M, typename C>
+  int BinHeap<K,V,M,C>::bubble_down(int hole, PairType p, int length) {
+    int child = second_child(hole);
+    while(child < length) {
+      if( less(data[child-1], data[child]) ) {
+	--child;
+      }
+      if( !less(data[child], p) )
+	goto ok;
+      move(data[child], hole);
+      hole = child;
+      child = second_child(hole);
+    }
+    child--;
+    if( child<length && less(data[child], p) ) {
+      move(data[child], hole);
+      hole=child;
+    }
+  ok:
+    move(p, hole);
+    return hole;
+  }
+
+  ///@}
+
+} // namespace lemon
+
+#endif // LEMON_BIN_HEAP_H