--- /dev/null
+// -*- C++ -*-
+
+// Copyright (C) 2005, 2006, 2009 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 3, 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 COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+
+// 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 erase_if_example.cpp
+ * A basic example showing how to use erase_if.
+ */
+
+/**
+ * The following example shows how to use a conditional-erase
+ * method of associative containers to erase some of their entries.
+ */
+
+#include <iostream>
+#include <cassert>
+#include <ext/pb_ds/assoc_container.hpp>
+
+using namespace std;
+using namespace __gnu_pbds;
+
+// The following functor takes a map's value-type object and returns
+// whether its key is between two numbers.
+struct between : public unary_function<pair<const int, char>, bool>
+{
+ // Constructor taking two numbers determining a range.
+ between(int b, int e) : m_b(b), m_e(e)
+ { assert(m_b < m_e); }
+
+ // Operator determining whether a value-type object's key is within
+ // the range.
+ inline bool
+ operator()(const pair<const int, char>& r_val)
+ { return r_val.first >= m_b&& r_val.first < m_e; }
+
+private:
+ const int m_b;
+ const int m_e;
+};
+
+/**
+ * The following function performs a sequence of operations on an
+ * associative container object mapping integers to characters. Specifically
+ * it inserts 100 values and then uses a conditional-erase method to erase
+ * the values whose key is between 10 and 90.
+ */
+template<class Cntnr>
+void
+some_op_sequence(Cntnr r_c)
+{
+ assert(r_c.empty());
+ assert(r_c.size() == 0);
+
+ for (int i = 0; i < 100; ++i)
+ r_c.insert(make_pair(i, static_cast<char>(i)));
+ assert(r_c.size() == 100);
+
+ // Erase all values whose key is between 10 (inclusive) and 90
+ // (non-inclusive).
+ r_c.erase_if(between(10 , 90));
+
+ assert(!r_c.empty());
+ assert(r_c.size() == 20);
+}
+
+int main()
+{
+ // Perform operations on a list-update set.
+ some_op_sequence(list_update<int, char>());
+
+ // Perform operations on a collision-chaining hash set.
+ some_op_sequence(cc_hash_table<int, char>());
+
+ // Perform operations on a general-probing hash set.
+ some_op_sequence(gp_hash_table<int, char>());
+
+ // Perform operations on a red-black tree set.
+ some_op_sequence(tree<int, char>());
+
+ // Perform operations on a splay tree set.
+ some_op_sequence(tree<
+ int,
+ char,
+ less<int>,
+ splay_tree_tag>());
+
+ // Perform operations on a splay tree set.
+ some_op_sequence(tree<
+ int,
+ char,
+ less<int>,
+ ov_tree_tag>());
+
+ return 0;
+}
projects / msp430-gcc.git / blobdiff