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			242 lines
		
	
	
		
			8.4 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			242 lines
		
	
	
		
			8.4 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
//  (C) Copyright Herve Bronnimann 2004.
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//  Use, modification and distribution are subject to the
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//  Boost Software License, Version 1.0. (See accompanying file
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//  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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#include <utility>
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#include <functional>
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#include <algorithm>
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#include <numeric>
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#include <iterator>
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#include <vector>
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#include <list>
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#include <set>
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#include <cstdlib>
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#include <boost/config.hpp> /* prevents some nasty warns in MSVC */
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#include <boost/algorithm/minmax_element.hpp>
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#include <boost/test/included/test_exec_monitor.hpp>
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#include <boost/iterator/reverse_iterator.hpp>
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class custom {
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  int m_x;
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  friend bool operator<(custom const& x, custom const& y);
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public:
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  explicit custom(int x = 0) : m_x(x) {}
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  custom(custom const& y) : m_x(y.m_x) {}
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  custom operator+(custom const& y) const { return custom(m_x+y.m_x); }
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  custom& operator+=(custom const& y) { m_x += y.m_x; return *this; }
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};
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bool operator< (custom const& x, custom const& y)
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{
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  return x.m_x < y.m_x;
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}
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BOOST_BROKEN_COMPILER_TYPE_TRAITS_SPECIALIZATION(custom)
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namespace std {
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template <>
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struct iterator_traits<int*> {
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  typedef random_access_iterator_tag  iterator_category;
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  typedef int                          value_type;
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  typedef ptrdiff_t                    difference_type;
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  typedef value_type*                  pointer;
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  typedef value_type&                  reference;
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};
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template <>
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struct iterator_traits<custom*> {
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  typedef random_access_iterator_tag  iterator_category;
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  typedef custom                       value_type;
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  typedef ptrdiff_t                    difference_type;
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  typedef value_type*                  pointer;
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  typedef value_type&                  reference;
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};
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}
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template <class T1, class T2, class T3, class T4>
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void tie(std::pair<T1, T2> p, T3& first, T4& second)
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{
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  first = T3(p.first); second = T4(p.second);
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}
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template <class Value>
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struct less_count : std::less<Value> {
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    typedef std::less<Value> Base;
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  less_count(less_count<Value> const& lc) : m_counter(lc.m_counter) {}
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  less_count(int& counter) : m_counter(counter) {}
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  bool operator()(Value const& a, Value const& b) const {
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    ++m_counter;
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    return Base::operator()(a,b);
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  }
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  void reset() {
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    m_counter = 0;
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  }
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private:
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  int& m_counter;
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};
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inline int opt_min_count(int n) {
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  return (n==0) ? 0 : n-1;
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}
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inline int opt_minmax_count(int n) {
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  if (n < 2) return 0;
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  if (n == 2) return 2;
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  return (n%2 == 0) ? 3*(n/2)-1 : 3*(n/2)+1;
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}
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inline int opt_boost_minmax_count(int n) {
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  if (n < 2) return 0;
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  if (n == 2) return 1;
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  return (n%2 == 0) ? 3*(n/2)-2 : 3*(n/2);
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}
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#define CHECK_EQUAL_ITERATORS( left, right, first ) \
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BOOST_CHECK_EQUAL( std::distance( first, left ), std::distance( first, right ) )
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template <class CIterator>
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void test_minmax(CIterator first, CIterator last, int n)
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{
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  using namespace boost;
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  typedef typename std::iterator_traits<CIterator>::value_type Value;
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  typedef boost::reverse_iterator<CIterator> RCIterator;
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  // assume that CIterator is BidirectionalIter
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  CIterator min, max;
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  RCIterator rfirst(last), rlast(first), rmin, rmax;
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  int counter = 0;
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  less_count<Value> lc(counter);
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  // standard extensions
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  // first version, operator<
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  tie( boost::minmax_element(first, last), min, max );
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  CHECK_EQUAL_ITERATORS( min, std::min_element(first, last), first );
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  CHECK_EQUAL_ITERATORS( max, std::max_element(first, last), first );
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  // second version, comp function object (keeps a counter!)
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  lc.reset();
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  tie( boost::minmax_element(first, last, lc), min, max );
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  BOOST_CHECK( counter <= opt_minmax_count(n) );
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  CHECK_EQUAL_ITERATORS( min, std::min_element(first, last, lc), first );
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  CHECK_EQUAL_ITERATORS( max, std::max_element(first, last, lc), first );
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  // boost extensions
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  // first version, operator<
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  CHECK_EQUAL_ITERATORS( boost::first_min_element(first, last), std::min_element(first, last), first );
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  rmin = RCIterator(boost::last_min_element(first, last));
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  rmin = (rmin == rfirst) ? rlast : --rmin;
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  CHECK_EQUAL_ITERATORS( rmin, std::min_element(rfirst, rlast), rfirst );
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  CHECK_EQUAL_ITERATORS( boost::first_max_element(first, last), std::max_element(first, last), first );
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  rmax = RCIterator(boost::last_max_element(first, last));
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  rmax = (rmax == rfirst) ? rlast : --rmax;
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  CHECK_EQUAL_ITERATORS( rmax, std::max_element(rfirst, rlast), rfirst );
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  tie( boost::first_min_last_max_element(first, last), min, max );
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  CHECK_EQUAL_ITERATORS( min, boost::first_min_element(first, last), first );
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  CHECK_EQUAL_ITERATORS( max, boost::last_max_element(first, last), first );
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  tie( boost::last_min_first_max_element(first, last), min, max );
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  CHECK_EQUAL_ITERATORS( min, boost::last_min_element(first, last), first );
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  CHECK_EQUAL_ITERATORS( max, boost::first_max_element(first, last), first );
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  tie( boost::last_min_last_max_element(first, last), min, max );
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  CHECK_EQUAL_ITERATORS( min, boost::last_min_element(first, last), first );
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  CHECK_EQUAL_ITERATORS( max, boost::last_max_element(first, last), first );
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  // second version, comp function object (keeps a counter!)
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  lc.reset();
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  min = boost::first_min_element(first, last, lc);
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  BOOST_CHECK( counter <= opt_min_count(n) );
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  CHECK_EQUAL_ITERATORS( min, std::min_element(first, last, lc), first );
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  lc.reset();
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  rmin = RCIterator(boost::last_min_element(first, last, lc));
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  rmin = (rmin == rfirst) ? rlast : --rmin;
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  BOOST_CHECK( counter <= opt_min_count(n) );
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  CHECK_EQUAL_ITERATORS( rmin, std::min_element(rfirst, rlast, lc), rfirst );
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  lc.reset();
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  max =  boost::first_max_element(first, last, lc);
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  BOOST_CHECK( counter <= opt_min_count(n) );
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  CHECK_EQUAL_ITERATORS( max, std::max_element(first, last, lc), first );
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  lc.reset();
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  rmax = RCIterator(boost::last_max_element(first, last, lc));
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  rmax = (rmax == rfirst) ? rlast : --rmax;
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  BOOST_CHECK( counter <= opt_min_count(n) );
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  CHECK_EQUAL_ITERATORS( rmax, std::max_element(rfirst, rlast, lc), rfirst );
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  lc.reset();
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  tie( boost::first_min_last_max_element(first, last, lc), min, max );
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  BOOST_CHECK( counter <= opt_boost_minmax_count(n) );
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  CHECK_EQUAL_ITERATORS( min, boost::first_min_element(first, last, lc), first );
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  CHECK_EQUAL_ITERATORS( max, boost::last_max_element(first, last, lc), first );
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  lc.reset();
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  tie( boost::last_min_first_max_element(first, last, lc), min, max );
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  BOOST_CHECK( counter <= opt_boost_minmax_count(n) );
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  BOOST_CHECK( min == boost::last_min_element(first, last, lc) );
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  CHECK_EQUAL_ITERATORS( max, boost::first_max_element(first, last, lc), first );
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  lc.reset();
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  tie( boost::last_min_last_max_element(first, last, lc), min, max );
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  BOOST_CHECK( counter <= opt_minmax_count(n) );
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  CHECK_EQUAL_ITERATORS( min, boost::last_min_element(first, last, lc), first );
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  CHECK_EQUAL_ITERATORS( max, boost::last_max_element(first, last, lc), first );
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}
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template <class Container, class Iterator, class Value>
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void test_container(Iterator first, Iterator last, int n,
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                    Container* dummy = 0
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                    BOOST_APPEND_EXPLICIT_TEMPLATE_TYPE(Value) )
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{
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  Container c(first, last);
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  test_minmax(c.begin(), c.end(), n);
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}
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template <class Iterator>
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void test_range(Iterator first, Iterator last, int n)
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{
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  typedef typename std::iterator_traits<Iterator>::value_type Value;
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  // Test various containers with these values
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  test_container< std::vector<Value>, Iterator, Value >(first, last, n);
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  test_container< std::list<Value>,   Iterator, Value >(first, last, n);
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  test_container< std::set<Value>,    Iterator, Value >(first, last, n);
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}
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template <class Value>
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void test(int n BOOST_APPEND_EXPLICIT_TEMPLATE_TYPE(Value))
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{
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  // Populate test vector with identical values
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  std::vector<Value> test_vector(n, Value(1));
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  typename std::vector<Value>::iterator first( test_vector.begin() );
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  typename std::vector<Value>::iterator last( test_vector.end() );
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  test_range(first, last, n);
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  // Populate test vector with two values
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  typename std::vector<Value>::iterator middle( first + n/2 );
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  std::fill(middle, last, Value(2));
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  test_range(first, last, n);
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  // Populate test vector with increasing values
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  std::accumulate(first, last, Value(0));
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  test_range(first, last, n);
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  // Populate test vector with decreasing values
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  std::reverse(first, last);
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  test_range(first, last, n);
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  // Populate test vector with random values
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  std::random_shuffle(first, last);
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  test_range(first, last, n);
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}
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int test_main( int argc, char* argv[] )
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{
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#ifndef BOOST_NO_STDC_NAMESPACE
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  using std::atoi;
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#endif
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  int n = 100;
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  if (argc > 1) n = atoi(argv[1]);
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  test<int>(n);
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  test<custom>(n);
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  return 0;
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}
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