diff options
Diffstat (limited to 'libs/algorithm/example')
-rw-r--r-- | libs/algorithm/example/Jamfile.v2 | 22 | ||||
-rw-r--r-- | libs/algorithm/example/clamp_example.cpp | 54 | ||||
-rw-r--r-- | libs/algorithm/example/search_example.cpp | 57 |
3 files changed, 133 insertions, 0 deletions
diff --git a/libs/algorithm/example/Jamfile.v2 b/libs/algorithm/example/Jamfile.v2 new file mode 100644 index 000000000..1d8e3b59f --- /dev/null +++ b/libs/algorithm/example/Jamfile.v2 @@ -0,0 +1,22 @@ +# Boost algorithm library example programs Jamfile +# +# Copyright Marshall Clow 2010-2012. Use, modification and +# distribution is subject to 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) +# +# See http://www.boost.org for updates, documentation, and revision history. + + +project /boost/algorithm/example + : requirements + <include>../../../ + <optimization>speed + <toolset>msvc:<define>_SCL_SECURE_NO_WARNINGS + <toolset>msvc:<define>NOMINMAX + <link>static + : + ; + +exe clamp_example : clamp_example.cpp ; +exe search_example : search_example.cpp ; diff --git a/libs/algorithm/example/clamp_example.cpp b/libs/algorithm/example/clamp_example.cpp new file mode 100644 index 000000000..be61c84c0 --- /dev/null +++ b/libs/algorithm/example/clamp_example.cpp @@ -0,0 +1,54 @@ +/* + 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 +*/ + +#include <string> +#include <iostream> // for cout, etc + +#include <boost/algorithm/clamp.hpp> + +namespace ba = boost::algorithm; + +bool compare_string_lengths ( const std::string &one, const std::string &two ) +{ + return one.length () < two.length (); +} + +int main ( int /*argc*/, char * /*argv*/ [] ) { +// Clamp takes a value and two "fenceposts", and brings the value "between" the fenceposts. + +// If the input value is "between" the fenceposts, then it is returned unchanged. + std::cout << "Clamping 5 to between [1, 10] -> " << ba::clamp ( 5, 1, 10 ) << std::endl; + +// If the input value is out side the range of the fenceposts, it "brought into" range. + std::cout << "Clamping 15 to between [1, 10] -> " << ba::clamp ( 15, 1, 10 ) << std::endl; + std::cout << "Clamping -15 to between [1, 10] -> " << ba::clamp ( -15, 1, 10 ) << std::endl; + +// It doesn't just work for ints + std::cout << "Clamping 5.1 to between [1, 10] -> " << ba::clamp ( 5.1, 1.0, 10.0 ) << std::endl; + + { + std::string one ( "Lower Bound" ), two ( "upper bound!" ), test1 ( "test#" ), test2 ( "#test" ); + std::cout << "Clamping '" << test1 << "' between ['" << one << "' and '" << two << "'] -> '" << + ba::clamp ( test1, one, two ) << "'" << std::endl; + std::cout << "Clamping '" << test2 << "' between ['" << one << "' and '" << two << "'] -> '" << + ba::clamp ( test2, one, two ) << "'" << std::endl; + // There is also a predicate based version, if you want to compare objects in your own way + std::cout << "Clamping '" << test1 << "' between ['" << one << "' and '" << two << "'] (comparing lengths) -> '" << + ba::clamp ( test1, one, two, compare_string_lengths ) << "'" << std::endl; + std::cout << "Clamping '" << test2 << "' between ['" << one << "' and '" << two << "'] (comparing lengths) -> '" << + ba::clamp ( test2, one, two, compare_string_lengths ) << "'" << std::endl; + + } + +// Sometimes, though, you don't get quite what you expect +// This is because the two double arguments get converted to int + std::cout << "Somewhat unexpected: clamp ( 12, 14.7, 15.9 ) --> " << ba::clamp ( 12, 14.7, 15.9 ) << std::endl; + std::cout << "Expected: clamp ((double)12, 14.7, 15.9 ) --> " << ba::clamp ((double) 12, 14.7, 15.9 ) << std::endl; + return 0; + } diff --git a/libs/algorithm/example/search_example.cpp b/libs/algorithm/example/search_example.cpp new file mode 100644 index 000000000..438bee9ad --- /dev/null +++ b/libs/algorithm/example/search_example.cpp @@ -0,0 +1,57 @@ +/* + 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 +*/ + +#include <string> +#include <iostream> // for cout, etc. + +#include <boost/algorithm/searching/boyer_moore.hpp> +#include <boost/algorithm/searching/boyer_moore_horspool.hpp> +#include <boost/algorithm/searching/knuth_morris_pratt.hpp> + +namespace ba = boost::algorithm; + +const std::string haystack ( "ABACAB is it everywhere!" ); +const std::string needle1 ( "ACAB" ); +const std::string needle2 ( "not ABA" ); + + + +int main ( int /*argc*/, char * /*argv*/ [] ) { +// In search.hpp, there are generic implementations of three classic sequence search +// algorithms. They all have the same (dual) interface. + +// There is a procedural interface, based on std::search: + if ( ba::boyer_moore_search ( haystack.begin (), haystack.end (), needle1.begin (), needle1.end ()) != haystack.end ()) + std::cout << "Found '" << needle1 << "' in '" << haystack << "' (boyer-moore 1)" << std::endl; + else + std::cout << "Did NOT find '" << needle1 << "' in '" << haystack << "' (boyer-moore 1)" << std::endl; + +// If you plan on searching for the same pattern in several different data sets, +// you can create a search object and use that over and over again - amortizing the setup +// costs across several searches + ba::boyer_moore<std::string::const_iterator> search1 ( needle1.begin (), needle1.end ()); + if ( search1 ( haystack.begin (), haystack.end ()) != haystack.end ()) + std::cout << "Found '" << needle1 << "' in '" << haystack << "' (boyer-moore 2)" << std::endl; + else + std::cout << "Did NOT find '" << needle1 << "' in '" << haystack << "' (boyer-moore 2)" << std::endl; + +// There is also an implementation of boyer-moore-horspool searching + if ( ba::boyer_moore_horspool_search ( haystack.begin (), haystack.end (), needle1.begin (), needle1.end ()) != haystack.end ()) + std::cout << "Found '" << needle1 << "' in '" << haystack << "' (boyer-moore-horspool)" << std::endl; + else + std::cout << "Did NOT find '" << needle1 << "' in '" << haystack << "' (boyer-moore-horspool)" << std::endl; + +// And also the knuth-pratt-morris search algorithm + if ( ba::knuth_morris_pratt_search ( haystack.begin (), haystack.end (), needle1.begin (), needle1.end ()) != haystack.end ()) + std::cout << "Found '" << needle1 << "' in '" << haystack << "' (knuth_morris_pratt)" << std::endl; + else + std::cout << "Did NOT find '" << needle1 << "' in '" << haystack << "' (knuth_morris_pratt)" << std::endl; + + return 0; + } |