// -*- C++ -*- // Copyright (C) 2005, 2006 Free Software Foundation, Inc. // // This file is part of the GNU ISO C++ Library. This library is free // software; you can redistribute it and/or modify it under the terms // of the GNU General Public License as published by the Free Software // Foundation; either version 2, or (at your option) any later // version. // This library is distributed in the hope that it will be useful, but // WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU // General Public License for more details. // You should have received a copy of the GNU General Public License // along with this library; see the file COPYING. If not, write to // the Free Software Foundation, 59 Temple Place - Suite 330, Boston, // MA 02111-1307, USA. // As a special exception, you may use this file as part of a free // software library without restriction. Specifically, if other files // instantiate templates or use macros or inline functions from this // file, or you compile this file and link it with other files to // produce an executable, this file does not by itself cause the // resulting executable to be covered by the GNU General Public // License. This exception does not however invalidate any other // reasons why the executable file might be covered by the GNU General // Public License. // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL. // Permission to use, copy, modify, sell, and distribute this software // is hereby granted without fee, provided that the above copyright // notice appears in all copies, and that both that copyright notice // and this permission notice appear in supporting documentation. None // of the above authors, nor IBM Haifa Research Laboratories, make any // representation about the suitability of this software for any // purpose. It is provided "as is" without express or implied // warranty. /** * @file tree_order_statistics_example.cpp * An example showing how to use functors for order-statistics * in tree-based containers. */ /** * In some cases tree structure can be used for various purposes asides * from storing entries by key order. * This example shows how a tree-based container can be used for * order-statistics, i.e., for determining the order of each key * in the (ordered) sequence of keys stored within the container object. */ #include <cassert> #include <ext/pb_ds/assoc_container.hpp> #include <ext/pb_ds/tree_policy.hpp> using namespace std; using namespace pb_ds; using namespace pb_ds; // A red-black tree table storing ints and their order // statistics. Note that since the tree uses // tree_order_statistics_node_update as its update policy, then it // includes its methods by_order and order_of_key. typedef tree< int, null_mapped_type, less<int>, rb_tree_tag, // This policy updates nodes' metadata for order statistics. tree_order_statistics_node_update> set_t; int main() { // Insert some entries into s. set_t s; s.insert(12); s.insert(505); s.insert(30); s.insert(1000); s.insert(10000); s.insert(100); // The order of the keys should be: 12, 30, 100, 505, 1000, 10000. assert(*s.find_by_order(0) == 12); assert(*s.find_by_order(1) == 30); assert(*s.find_by_order(2) == 100); assert(*s.find_by_order(3) == 505); assert(*s.find_by_order(4) == 1000); assert(*s.find_by_order(5) == 10000); assert(s.find_by_order(6) == s.end()); // The order of the keys should be: 12, 30, 100, 505, 1000, 10000. assert(s.order_of_key(10) == 0); assert(s.order_of_key(12) == 0); assert(s.order_of_key(15) == 1); assert(s.order_of_key(30) == 1); assert(s.order_of_key(99) == 2); assert(s.order_of_key(100) == 2); assert(s.order_of_key(505) == 3); assert(s.order_of_key(1000) == 4); assert(s.order_of_key(10000) == 5); assert(s.order_of_key(9999999) == 6); // Erase an entry. s.erase(30); // The order of the keys should be: 12, 100, 505, 1000, 10000. assert(*s.find_by_order(0) == 12); assert(*s.find_by_order(1) == 100); assert(*s.find_by_order(2) == 505); assert(*s.find_by_order(3) == 1000); assert(*s.find_by_order(4) == 10000); assert(s.find_by_order(5) == s.end()); // The order of the keys should be: 12, 100, 505, 1000, 10000. assert(s.order_of_key(10) == 0); assert(s.order_of_key(12) == 0); assert(s.order_of_key(100) == 1); assert(s.order_of_key(505) == 2); assert(s.order_of_key(707) == 3); assert(s.order_of_key(1000) == 3); assert(s.order_of_key(1001) == 4); assert(s.order_of_key(10000) == 4); assert(s.order_of_key(100000) == 5); assert(s.order_of_key(9999999) == 5); return 0; }