comparison DEPENDENCIES/generic/include/boost/pending/mutable_queue.hpp @ 16:2665513ce2d3

Add boost headers

+//
+//=======================================================================
+// Copyright 1997, 1998, 1999, 2000 University of Notre Dame.
+// Authors: Andrew Lumsdaine, Lie-Quan Lee, Jeremy G. Siek
+//
+// Distributed under the Boost Software License, Version 1.0. (See
+// accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+//=======================================================================
+//
+#ifndef BOOST_MUTABLE_QUEUE_HPP
+#define BOOST_MUTABLE_QUEUE_HPP
+
+#include <vector>
+#include <algorithm>
+#include <functional>
+#include <boost/property_map/property_map.hpp>
+#include <boost/pending/mutable_heap.hpp>
+#include <boost/pending/is_heap.hpp>
+#include <boost/graph/detail/array_binary_tree.hpp>
+#include <iterator>
+
+namespace boost {
+
+  // The mutable queue whose elements are indexed
+  //
+  // This adaptor provides a special kind of priority queue that has
+  // and update operation. This allows the ordering of the items to
+  // change. After the ordering criteria for item x changes, one must
+  // call the Q.update(x)
+  //
+  // In order to efficiently find x in the queue, a functor must be
+  // provided to map value_type to a unique ID, which the
+  // mutable_queue will then use to map to the location of the
+  // item. The ID's generated must be between 0 and N, where N is the
+  // value passed to the constructor of mutable_queue
+
+  template <class IndexedType,
+            class RandomAccessContainer = std::vector<IndexedType>,
+            class Comp = std::less<typename RandomAccessContainer::value_type>,
+            class ID = identity_property_map >
+  class mutable_queue {
+  public:
+    typedef IndexedType value_type;
+    typedef typename RandomAccessContainer::size_type size_type;
+  protected:
+    typedef typename RandomAccessContainer::iterator iterator;
+#if !defined BOOST_NO_STD_ITERATOR_TRAITS
+    typedef array_binary_tree_node<iterator, ID> Node;
+#else
+    typedef array_binary_tree_node<iterator, value_type, ID> Node;
+#endif
+    typedef compare_array_node<RandomAccessContainer,Comp> Compare;
+    typedef std::vector<size_type> IndexArray;
+  public:
+    typedef Compare value_compare;
+    typedef ID id_generator;
+
+    mutable_queue(size_type n, const Comp& x, const ID& _id)
+      : index_array(n), comp(x), id(_id) {
+      c.reserve(n);
+    }
+    template <class ForwardIterator>
+    mutable_queue(ForwardIterator first, ForwardIterator last,
+                  const Comp& x, const ID& _id)
+      : index_array(std::distance(first, last)), comp(x), id(_id)
+    {
+      while( first != last ) {
+        push(*first);
+        ++first;
+      }
+    }
+
+    bool empty() const { return c.empty(); }
+
+    void pop() {
+      value_type tmp = c.back();
+      c.back() = c.front();
+      c.front() = tmp;
+
+      size_type id_f = get(id, c.back());
+      size_type id_b = get(id, tmp);
+      size_type i = index_array[ id_b ];
+      index_array[ id_b ] = index_array[ id_f ];
+      index_array[ id_f ] = i;
+
+      c.pop_back();
+      Node node(c.begin(), c.end(), c.begin(), id);
+      down_heap(node, comp, index_array);
+    }
+    void push(const IndexedType& x) {
+      c.push_back(x);
+      /*set index-array*/
+      index_array[ get(id, x) ] = c.size()-1;
+      Node node(c.begin(), c.end(), c.end() - 1, id);
+      up_heap(node, comp, index_array);
+    }
+
+    void update(const IndexedType& x) {
+      size_type current_pos = index_array[ get(id, x) ];
+      c[current_pos] = x;
+
+      Node node(c.begin(), c.end(), c.begin()+current_pos, id);
+      update_heap(node, comp, index_array);
+    }
+
+    value_type& front() { return c.front(); }
+    value_type& top() { return c.front(); }
+
+    const value_type& front() const { return c.front(); }
+    const value_type& top() const { return c.front(); }
+
+    size_type size() const { return c.size(); }
+
+    void clear() { c.clear(); }
+
+#if 0
+        // dwa 2003/7/11 - I don't know what compiler is supposed to
+        // be able to compile this, but is_heap is not standard!!
+    bool test() {
+      return std::is_heap(c.begin(), c.end(), Comp());
+    }
+#endif
+
+   protected:
+    IndexArray index_array;
+    Compare comp;
+    RandomAccessContainer c;
+    ID id;
+  };
+
+
+}
+
+#endif // BOOST_MUTABLE_QUEUE_HPP