Added thirdparty: boost library

thirdparty/include/boost/pending/disjoint_sets.hpp

@@ -0,0 +1,211 @@
+//
+//=======================================================================
+// 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_DISJOINT_SETS_HPP
+#define BOOST_DISJOINT_SETS_HPP
+
+#include <vector>
+#include <boost/graph/properties.hpp>
+#include <boost/pending/detail/disjoint_sets.hpp>
+
+namespace boost
+{
+
+struct find_with_path_halving
+{
+    template < class ParentPA, class Vertex >
+    Vertex operator()(ParentPA p, Vertex v)
+    {
+        return detail::find_representative_with_path_halving(p, v);
+    }
+};
+
+struct find_with_full_path_compression
+{
+    template < class ParentPA, class Vertex >
+    Vertex operator()(ParentPA p, Vertex v)
+    {
+        return detail::find_representative_with_full_compression(p, v);
+    }
+};
+
+// This is a generalized functor to provide disjoint sets operations
+// with "union by rank" and "path compression".  A disjoint-set data
+// structure maintains a collection S={S1, S2, ..., Sk} of disjoint
+// sets. Each set is identified by a representative, which is some
+// member of of the set. Sets are represented by rooted trees. Two
+// heuristics: "union by rank" and "path compression" are used to
+// speed up the operations.
+
+// Disjoint Set requires two vertex properties for internal use.  A
+// RankPA and a ParentPA. The RankPA must map Vertex to some Integral type
+// (preferably the size_type associated with Vertex). The ParentPA
+// must map Vertex to Vertex.
+template < class RankPA, class ParentPA,
+    class FindCompress = find_with_full_path_compression >
+class disjoint_sets
+{
+    typedef disjoint_sets self;
+
+    inline disjoint_sets() {}
+
+public:
+    inline disjoint_sets(RankPA r, ParentPA p) : rank(r), parent(p) {}
+
+    inline disjoint_sets(const self& c) : rank(c.rank), parent(c.parent) {}
+
+    // Make Set -- Create a singleton set containing vertex x
+    template < class Element > inline void make_set(Element x)
+    {
+        put(parent, x, x);
+        typedef typename property_traits< RankPA >::value_type R;
+        put(rank, x, R());
+    }
+
+    // Link - union the two sets represented by vertex x and y
+    template < class Element > inline void link(Element x, Element y)
+    {
+        detail::link_sets(parent, rank, x, y, rep);
+    }
+
+    // Union-Set - union the two sets containing vertex x and y
+    template < class Element > inline void union_set(Element x, Element y)
+    {
+        link(find_set(x), find_set(y));
+    }
+
+    // Find-Set - returns the Element representative of the set
+    // containing Element x and applies path compression.
+    template < class Element > inline Element find_set(Element x)
+    {
+        return rep(parent, x);
+    }
+
+    template < class ElementIterator >
+    inline std::size_t count_sets(ElementIterator first, ElementIterator last)
+    {
+        std::size_t count = 0;
+        for (; first != last; ++first)
+            if (get(parent, *first) == *first)
+                ++count;
+        return count;
+    }
+
+    template < class ElementIterator >
+    inline void normalize_sets(ElementIterator first, ElementIterator last)
+    {
+        for (; first != last; ++first)
+            detail::normalize_node(parent, *first);
+    }
+
+    template < class ElementIterator >
+    inline void compress_sets(ElementIterator first, ElementIterator last)
+    {
+        for (; first != last; ++first)
+            detail::find_representative_with_full_compression(parent, *first);
+    }
+
+protected:
+    RankPA rank;
+    ParentPA parent;
+    FindCompress rep;
+};
+
+template < class ID = identity_property_map,
+    class InverseID = identity_property_map,
+    class FindCompress = find_with_full_path_compression >
+class disjoint_sets_with_storage
+{
+    typedef typename property_traits< ID >::value_type Index;
+    typedef std::vector< Index > ParentContainer;
+    typedef std::vector< unsigned char > RankContainer;
+
+public:
+    typedef typename ParentContainer::size_type size_type;
+
+    disjoint_sets_with_storage(
+        size_type n = 0, ID id_ = ID(), InverseID inv = InverseID())
+    : id(id_), id_to_vertex(inv), rank(n, 0), parent(n)
+    {
+        for (Index i = 0; i < n; ++i)
+            parent[i] = i;
+    }
+    // note this is not normally needed
+    template < class Element > inline void make_set(Element x)
+    {
+        parent[x] = x;
+        rank[x] = 0;
+    }
+    template < class Element > inline void link(Element x, Element y)
+    {
+        extend_sets(x, y);
+        detail::link_sets(&parent[0], &rank[0], get(id, x), get(id, y), rep);
+    }
+    template < class Element > inline void union_set(Element x, Element y)
+    {
+        Element rx = find_set(x);
+        Element ry = find_set(y);
+        link(rx, ry);
+    }
+    template < class Element > inline Element find_set(Element x)
+    {
+        return id_to_vertex[rep(&parent[0], get(id, x))];
+    }
+
+    template < class ElementIterator >
+    inline std::size_t count_sets(ElementIterator first, ElementIterator last)
+    {
+        std::size_t count = 0;
+        for (; first != last; ++first)
+            if (parent[*first] == *first)
+                ++count;
+        return count;
+    }
+
+    template < class ElementIterator >
+    inline void normalize_sets(ElementIterator first, ElementIterator last)
+    {
+        for (; first != last; ++first)
+            detail::normalize_node(&parent[0], *first);
+    }
+
+    template < class ElementIterator >
+    inline void compress_sets(ElementIterator first, ElementIterator last)
+    {
+        for (; first != last; ++first)
+            detail::find_representative_with_full_compression(
+                &parent[0], *first);
+    }
+
+    const ParentContainer& parents() { return parent; }
+
+protected:
+    template < class Element > inline void extend_sets(Element x, Element y)
+    {
+        Index needed
+            = get(id, x) > get(id, y) ? get(id, x) + 1 : get(id, y) + 1;
+        if (needed > parent.size())
+        {
+            rank.insert(rank.end(), needed - rank.size(), 0);
+            for (Index k = parent.size(); k < needed; ++k)
+                parent.push_back(k);
+        }
+    }
+
+    ID id;
+    InverseID id_to_vertex;
+    RankContainer rank;
+    ParentContainer parent;
+    FindCompress rep;
+};
+
+} // namespace boost
+
+#endif // BOOST_DISJOINT_SETS_HPP