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// Boost.Bimap
//
// Copyright (c) 2006-2007 Matias Capeletto
//
// 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)
/*****************************************************************************
Boost.MultiIndex
*****************************************************************************/
#include <boost/config.hpp>
//[ code_mi_to_b_path_mi_hashed_indices
#include <iostream>
#include <iomanip>
#include <boost/tokenizer.hpp>
#include <boost/multi_index_container.hpp>
#include <boost/multi_index/key_extractors.hpp>
#include <boost/multi_index/ordered_index.hpp>
#include <boost/multi_index/hashed_index.hpp>
#include <boost/lambda/lambda.hpp>
using namespace boost::multi_index;
namespace bl = boost::lambda;
// word_counter keeps the ocurrences of words inserted. A hashed
// index allows for fast checking of preexisting entries.
struct word_counter_entry
{
std::string word;
unsigned int occurrences;
word_counter_entry( std::string word_ ) : word(word_), occurrences(0) {}
};
typedef multi_index_container
<
word_counter_entry,
indexed_by
<
ordered_non_unique
<
BOOST_MULTI_INDEX_MEMBER(
word_counter_entry,unsigned int,occurrences),
std::greater<unsigned int>
>,
hashed_unique
<
BOOST_MULTI_INDEX_MEMBER(word_counter_entry,std::string,word)
>
>
> word_counter;
typedef boost::tokenizer<boost::char_separator<char> > text_tokenizer;
int main()
{
std::string text=
"En un lugar de la Mancha, de cuyo nombre no quiero acordarme... "
"...snip..."
"...no se salga un punto de la verdad.";
// feed the text into the container
word_counter wc;
text_tokenizer tok(text,boost::char_separator<char>(" \t\n.,;:!?'\"-"));
unsigned int total_occurrences = 0;
for( text_tokenizer::iterator it = tok.begin(), it_end = tok.end();
it != it_end ; ++it )
{
++total_occurrences;
word_counter::iterator wit = wc.insert(*it).first;
wc.modify_key( wit, ++ bl::_1 );
}
// list words by frequency of appearance
std::cout << std::fixed << std::setprecision(2);
for( word_counter::iterator wit = wc.begin(), wit_end=wc.end();
wit != wit_end; ++wit )
{
std::cout << std::setw(11) << wit->word << ": "
<< std::setw(5)
<< 100.0 * wit->occurrences / total_occurrences << "%"
<< std::endl;
}
return 0;
}
//]
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