bimap/example/repetitions_counter.cpp
2019-04-23 14:10:01 +02:00

92 lines
3.0 KiB
C++

// 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)
// VC++ 8.0 warns on usage of certain Standard Library and API functions that
// can be cause buffer overruns or other possible security issues if misused.
// See https://web.archive.org/web/20071014014301/http://msdn.microsoft.com/msdnmag/issues/05/05/SafeCandC/default.aspx
// But the wording of the warning is misleading and unsettling, there are no
// portable alternative functions, and VC++ 8.0's own libraries use the
// functions in question. So turn off the warnings.
#define _CRT_SECURE_NO_DEPRECATE
#define _SCL_SECURE_NO_DEPRECATE
// Boost.Bimap Example
//-----------------------------------------------------------------------------
#include <boost/config.hpp>
#include <iostream>
#include <boost/tokenizer.hpp>
#include <boost/bimap/bimap.hpp>
#include <boost/bimap/unordered_set_of.hpp>
#include <boost/bimap/list_of.hpp>
using namespace boost::bimaps;
struct counter {
counter() : c(0) {}
counter& operator++() { ++c; return *this; }
unsigned int operator++(int) { return c++; }
operator const unsigned int() const { return c; }
private:
unsigned int c;
};
int main()
{
//[ code_repetitions_counter
typedef bimap
<
unordered_set_of< std::string >,
list_of< counter > /*< `counter` is an integer that is initialized
in zero in the constructor >*/
> word_counter;
typedef boost::tokenizer<boost::char_separator<char> > text_tokenizer;
std::string text=
"Relations between data in the STL are represented with maps."
"A map is a directed relation, by using it you are representing "
"a mapping. In this directed relation, the first type is related to "
"the second type but it is not true that the inverse relationship "
"holds. This is useful in a lot of situations, but there are some "
"relationships that are bidirectional by nature.";
// feed the text into the container
word_counter wc;
text_tokenizer tok(text,boost::char_separator<char>(" \t\n.,;:!?'\"-"));
for( text_tokenizer::const_iterator it = tok.begin(), it_end = tok.end();
it != it_end ; ++it )
{
/*<< Because the right collection type is `list_of`, the right data
is not used a key and can be modified in the same way as with
standard maps. >>*/
++ wc.left[*it];
}
// list words with counters by order of appearance
/*<< When we insert the elements using the left map view, the element
is inserted at the end of the list. >>*/
for( word_counter::right_const_iterator
wit = wc.right.begin(), wit_end = wc.right.end();
wit != wit_end; ++wit )
{
std::cout << wit->second << ": " << wit->first;
}
//]
return 0;
}