stxxl::sort()
algorithm
/*************************************************************************** * algo/test_sort.cpp * * Part of the STXXL. See http://stxxl.sourceforge.net * * Copyright (C) 2002 Roman Dementiev <[email protected]> * * 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) **************************************************************************/ #include <stxxl/mng> #include <stxxl/sort> #include <stxxl/vector> #define RECORD_SIZE 8 struct my_type { typedef unsigned key_type; key_type _key; char _data[RECORD_SIZE - sizeof(key_type)]; key_type key() const { return _key; } my_type() { } my_type(key_type __key) : _key(__key) { } static my_type min_value() { return my_type((std::numeric_limits<key_type>::min)()); } static my_type max_value() { return my_type((std::numeric_limits<key_type>::max)()); } ~my_type() { } }; std::ostream & operator << (std::ostream & o, const my_type & obj) { o << obj._key; return o; } bool operator < (const my_type & a, const my_type & b) { return a.key() < b.key(); } bool operator == (const my_type & a, const my_type & b) { return a.key() == b.key(); } bool operator != (const my_type & a, const my_type & b) { return a.key() != b.key(); } struct cmp : public std::less<my_type> { my_type min_value() const { return my_type::min_value(); } my_type max_value() const { return my_type::max_value(); } }; int main() { unsigned memory_to_use = 128 * 1024 * 1024; typedef stxxl::vector<my_type> vector_type; const stxxl::int64 n_records = stxxl::int64(384) * stxxl::int64(1024 * 1024) / sizeof(my_type); vector_type v(n_records); stxxl::random_number32 rnd; STXXL_MSG("Filling vector..., input size =" << v.size()); for (vector_type::size_type i = 0; i < v.size(); i++) v[i]._key = 1 + (rnd() % 0xfffffff); STXXL_MSG("Checking order..."); STXXL_MSG(((stxxl::is_sorted(v.begin(), v.end())) ? "OK" : "WRONG")); STXXL_MSG("Sorting..."); stxxl::sort(v.begin(), v.end(), cmp(), memory_to_use); STXXL_MSG("Checking order..."); STXXL_MSG(((stxxl::is_sorted(v.begin(), v.end())) ? "OK" : "WRONG")); STXXL_MSG("Done, output size=" << v.size()); return 0; }