projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 7c673cae FG |
1 | // |
| 2 | //======================================================================= | |
| 3 | // Copyright 1997, 1998, 1999, 2000 University of Notre Dame. | |
| 4 | // Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek | |
| 5 | // | |
| 6 | // Distributed under the Boost Software License, Version 1.0. (See | |
| 7 | // accompanying file LICENSE_1_0.txt or copy at | |
| 8 | // http://www.boost.org/LICENSE_1_0.txt) | |
| 9 | //======================================================================= | |
| 10 | // | |
| 11 | #ifndef BOOST_GRAPH_DETAIL_MUTABLE_HEAP_H | |
| 12 | #define BOOST_GRAPH_DETAIL_MUTABLE_HEAP_H | |
| 13 | ||
| 14 | /* | |
| 15 | There are a few things wrong with this set of functions. | |
| 16 | ||
| 17 | ExternalData should be removed, it is not part of the core | |
| 18 | algorithm. It can be handled inside the tree nodes. | |
| 19 | ||
| 20 | The swap() should be replaced by assignment since its use is causing | |
| 21 | the number of memory references to double. | |
| 22 | ||
| 23 | The min_element should be replaced by a fixed length loop | |
| 24 | (fixed at d for d-heaps). | |
| 25 | ||
| 26 | The member functions of TreeNode should be changed to global | |
| 27 | functions. | |
| 28 | ||
| 29 | These functions will be replaced by those in heap_tree.h | |
| 30 | ||
| 31 | */ | |
| 32 | ||
| 33 | namespace boost { | |
| 34 | ||
| 35 | template <class TreeNode, class Compare, class ExternalData> | |
| 36 | inline TreeNode up_heap(TreeNode x, const Compare& comp, ExternalData& edata) { | |
| 37 | while (x.has_parent() && comp(x, x.parent())) | |
| 38 | x.swap(x.parent(), edata); | |
| 39 | return x; | |
| 40 | } | |
| 41 | ||
| 42 | template <class TreeNode, class Compare, class ExternalData> | |
| 43 | inline TreeNode down_heap(TreeNode x, const Compare& comp, ExternalData& edata) { | |
| 44 | while (x.children().size() > 0) { | |
| 45 | typename TreeNode::children_type::iterator | |
| 46 | child_iter = std::min_element(x.children().begin(), | |
| 47 | x.children().end(), | |
| 48 | comp); | |
| 49 | if (comp(*child_iter, x)) | |
| 50 | x.swap(*child_iter, edata); | |
| 51 | else | |
| 52 | break; | |
| 53 | } | |
| 54 | return x; | |
| 55 | } | |
| 56 | ||
| 57 | template <class TreeNode, class Compare, class ExternalData> | |
| 58 | inline void update_heap(TreeNode x, const Compare& comp, ExternalData& edata) { | |
| 59 | x = down_heap(x, comp, edata); | |
| 60 | (void)up_heap(x, comp, edata); | |
| 61 | } | |
| 62 | ||
| 63 | } | |
| 64 | #endif |