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diff --git a/boost/algorithm/searching/detail/bm_traits.hpp b/boost/algorithm/searching/detail/bm_traits.hpp
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+++ b/boost/algorithm/searching/detail/bm_traits.hpp
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+/* 
+   Copyright (c) Marshall Clow 2010-2012.
+
+   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)
+
+    For more information, see http://www.boost.org
+*/
+
+#ifndef BOOST_ALGORITHM_SEARCH_DETAIL_BM_TRAITS_HPP
+#define BOOST_ALGORITHM_SEARCH_DETAIL_BM_TRAITS_HPP
+
+#include <climits>      // for CHAR_BIT
+#include <vector>
+#include <iterator>     // for std::iterator_traits
+
+#include <boost/type_traits/make_unsigned.hpp>
+#include <boost/type_traits/is_integral.hpp>
+#include <boost/type_traits/remove_pointer.hpp>
+#include <boost/type_traits/remove_const.hpp>
+
+#include <boost/array.hpp>
+#include <boost/tr1/tr1/unordered_map>
+
+#include <boost/algorithm/searching/detail/debugging.hpp>
+
+namespace boost { namespace algorithm { namespace detail {
+
+//
+//  Default implementations of the skip tables for B-M and B-M-H
+//
+    template<typename key_type, typename value_type, bool /*useArray*/> class skip_table;
+
+//  General case for data searching other than bytes; use a map
+    template<typename key_type, typename value_type>
+    class skip_table<key_type, value_type, false> {
+    private:
+        typedef std::tr1::unordered_map<key_type, value_type> skip_map;
+        const value_type k_default_value;
+        skip_map skip_;
+        
+    public:
+        skip_table ( std::size_t patSize, value_type default_value ) 
+            : k_default_value ( default_value ), skip_ ( patSize ) {}
+        
+        void insert ( key_type key, value_type val ) {
+            skip_ [ key ] = val;    // Would skip_.insert (val) be better here?
+            }
+
+        value_type operator [] ( key_type key ) const {
+            typename skip_map::const_iterator it = skip_.find ( key );
+            return it == skip_.end () ? k_default_value : it->second;
+            }
+            
+        void PrintSkipTable () const {
+            std::cout << "BM(H) Skip Table <unordered_map>:" << std::endl;
+            for ( typename skip_map::const_iterator it = skip_.begin (); it != skip_.end (); ++it )
+                if ( it->second != k_default_value )
+                    std::cout << "  " << it->first << ": " << it->second << std::endl;
+            std::cout << std::endl;
+            }
+        };
+        
+    
+//  Special case small numeric values; use an array
+    template<typename key_type, typename value_type>
+    class skip_table<key_type, value_type, true> {
+    private:
+        typedef typename boost::make_unsigned<key_type>::type unsigned_key_type;
+        typedef boost::array<value_type, 1U << (CHAR_BIT * sizeof(key_type))> skip_map;
+        skip_map skip_;
+        const value_type k_default_value;
+    public:
+        skip_table ( std::size_t patSize, value_type default_value ) : k_default_value ( default_value ) {
+            std::fill_n ( skip_.begin(), skip_.size(), default_value );
+            }
+        
+        void insert ( key_type key, value_type val ) {
+            skip_ [ static_cast<unsigned_key_type> ( key ) ] = val;
+            }
+
+        value_type operator [] ( key_type key ) const {
+            return skip_ [ static_cast<unsigned_key_type> ( key ) ];
+            }
+
+        void PrintSkipTable () const {
+            std::cout << "BM(H) Skip Table <boost:array>:" << std::endl;
+            for ( typename skip_map::const_iterator it = skip_.begin (); it != skip_.end (); ++it )
+                if ( *it != k_default_value )
+                    std::cout << "  " << std::distance (skip_.begin (), it) << ": " << *it << std::endl;
+            std::cout << std::endl;
+            }
+        };
+
+    template<typename Iterator>
+    struct BM_traits {
+        typedef typename std::iterator_traits<Iterator>::difference_type value_type;
+        typedef typename std::iterator_traits<Iterator>::value_type key_type;
+        typedef boost::algorithm::detail::skip_table<key_type, value_type, 
+                boost::is_integral<key_type>::value && (sizeof(key_type)==1)> skip_table_t;
+        };
+
+}}} // namespaces
+
+#endif  //  BOOST_ALGORITHM_SEARCH_DETAIL_BM_TRAITS_HPP