1.1 --- a/lemon/kary_heap.h Thu Jul 09 04:07:08 2009 +0200
1.2 +++ b/lemon/kary_heap.h Fri Jul 10 09:15:22 2009 +0200
1.3 @@ -45,15 +45,20 @@
1.4 /// \tparam PR Type of the priorities of the items.
1.5 /// \tparam IM A read-writable item map with \c int values, used
1.6 /// internally to handle the cross references.
1.7 + /// \tparam K The degree of the heap, each node have at most \e K
1.8 + /// children. The default is 16. Powers of two are suggested to use
1.9 + /// so that the multiplications and divisions needed to traverse the
1.10 + /// nodes of the heap could be performed faster.
1.11 /// \tparam CMP A functor class for comparing the priorities.
1.12 /// The default is \c std::less<PR>.
1.13 ///
1.14 ///\sa BinHeap
1.15 ///\sa FouraryHeap
1.16 #ifdef DOXYGEN
1.17 - template <typename PR, typename IM, typename CMP>
1.18 + template <typename PR, typename IM, int K, typename CMP>
1.19 #else
1.20 - template <typename PR, typename IM, typename CMP = std::less<PR> >
1.21 + template <typename PR, typename IM, int K = 16,
1.22 + typename CMP = std::less<PR> >
1.23 #endif
1.24 class KaryHeap {
1.25 public:
1.26 @@ -86,7 +91,6 @@
1.27 std::vector<Pair> _data;
1.28 Compare _comp;
1.29 ItemIntMap &_iim;
1.30 - int _K;
1.31
1.32 public:
1.33 /// \brief Constructor.
1.34 @@ -95,7 +99,7 @@
1.35 /// \param map A map that assigns \c int values to the items.
1.36 /// It is used internally to handle the cross references.
1.37 /// The assigned value must be \c PRE_HEAP (<tt>-1</tt>) for each item.
1.38 - explicit KaryHeap(ItemIntMap &map, int K=32) : _iim(map), _K(K) {}
1.39 + explicit KaryHeap(ItemIntMap &map) : _iim(map) {}
1.40
1.41 /// \brief Constructor.
1.42 ///
1.43 @@ -104,8 +108,8 @@
1.44 /// It is used internally to handle the cross references.
1.45 /// The assigned value must be \c PRE_HEAP (<tt>-1</tt>) for each item.
1.46 /// \param comp The function object used for comparing the priorities.
1.47 - KaryHeap(ItemIntMap &map, const Compare &comp, int K=32)
1.48 - : _iim(map), _comp(comp), _K(K) {}
1.49 + KaryHeap(ItemIntMap &map, const Compare &comp)
1.50 + : _iim(map), _comp(comp) {}
1.51
1.52 /// \brief The number of items stored in the heap.
1.53 ///
1.54 @@ -127,8 +131,8 @@
1.55 void clear() { _data.clear(); }
1.56
1.57 private:
1.58 - int parent(int i) { return (i-1)/_K; }
1.59 - int firstChild(int i) { return _K*i+1; }
1.60 + int parent(int i) { return (i-1)/K; }
1.61 + int firstChild(int i) { return K*i+1; }
1.62
1.63 bool less(const Pair &p1, const Pair &p2) const {
1.64 return _comp(p1.second, p2.second);
1.65 @@ -136,7 +140,7 @@
1.66
1.67 int findMin(const int child, const int length) {
1.68 int min=child, i=1;
1.69 - while( i<_K && child+i<length ) {
1.70 + while( i<K && child+i<length ) {
1.71 if( less(_data[child+i], _data[min]) )
1.72 min=child+i;
1.73 ++i;