1// -*- C++ -*-
2
3// Copyright (C) 2005 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library.  This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 2, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14// GNU General Public License for more details.
15
16// You should have received a copy of the GNU General Public License along
17// with this library; see the file COPYING.  If not, write to the Free
18// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
19// USA.
20
21// As a special exception, you may use this file as part of a free software
22// library without restriction.  Specifically, if other files instantiate
23// templates or use macros or inline functions from this file, or you compile
24// this file and link it with other files to produce an executable, this
25// file does not by itself cause the resulting executable to be covered by
26// the GNU General Public License.  This exception does not however
27// invalidate any other reasons why the executable file might be covered by
28// the GNU General Public License.
29
30// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
31
32// Permission to use, copy, modify, sell, and distribute this software
33// is hereby granted without fee, provided that the above copyright
34// notice appears in all copies, and that both that copyright notice and
35// this permission notice appear in supporting documentation. None of
36// the above authors, nor IBM Haifa Research Laboratories, make any
37// representation about the suitability of this software for any
38// purpose. It is provided "as is" without express or implied warranty.
39
40/**
41 * @file hash_mod_example.cpp
42 * An example showing how to use a mod range-hasing function
43 */
44
45// For cc_hash_assoc_cntnr.
46#include <ext/pb_assoc/assoc_cntnr.hpp>
47// For direct_mask_range_hashing and hash_standard_resize_policy.
48#include <ext/pb_assoc/hash_policy.hpp>
49// For unary_function, binary_function.
50#include <functional>
51/*
52 * A simple hash functor.
53 *	std::hash could serve instead of this functor,
54 *	but it is not yet standard everywhere.
55 */
56struct int_hash : public std::unary_function<
57  int,
58	     size_t>
59{
60  inline size_t
61  operator()(int i) const
62  {
63    return (i);
64  }
65};
66
67int
68main()
69{
70  /*
71   * A collision-chaining hash table mapping ints to chars.
72   */
73  typedef
74    pb_assoc::cc_hash_assoc_cntnr<
75    int,
76    char,
77    int_hash,
78    std::equal_to<int>,
79    // Combining function.
80    pb_assoc::direct_mod_range_hashing<> >
81    map_t;
82
83  map_t c;
84
85  c[32] = 'b';
86  c[1024] = 'c';
87  c[4096] = 'd';
88}
89
90