1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
|
// -*- C++ -*-
// Copyright (C) 2005-2016 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 tree_join_example.cpp
* An example showing how to join splay_tree_map objects.
* The code in the example is relevant to red-black trees as well.
*/
/**
* This example shows how to join tree based containers, i.e., taking two
* objects with non-overlapping sets of keys and combining them into
* a single object.
*/
// For tree
#include <ext/pb_ds/assoc_container.hpp>
// For join_error exception.
#include <ext/pb_ds/exception.hpp>
// For assert
#include <cassert>
using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_pbds;
int main()
{
/*
*
*/
// A splay tree table mapping ints to chars.
typedef tree<int, char, less<int>, splay_tree_tag> map_t;
// Two map_t object.
map_t h0, h1;
// Insert some values into the first table.
for (int i0 = 0; i0 < 100; ++i0)
h0.insert(make_pair(i0, 'a'));
// Insert some values into the second table.
for (int i1 = 0; i1 < 100; ++i1)
h1.insert(make_pair(1000 + i1, 'b'));
// Since all the elements in h0 are smaller than those in h1, it is
// possible to join the two tables. This is exception free.
h0.join(h1);
// Check that h0 should now contain all entries, and h1 should be empty.
assert(h0.size() == 200);
assert(h1.empty());
// Two other map_t objects.
map_t h2, h3;
h2[1] = 'a';
h2[3] = 'c';
h3[2] = 'b';
// Now perform an illegal join.
// It is not true that all elements in h2 are smaller than those in
// h3, nor is it true that they are all larger. Hence, attempting to
// join h2, and h3 should result in an exception.
bool exception_thrown = false;
try
{
h2.join(h3);
}
catch (__gnu_pbds::join_error& )
{
exception_thrown = true;
}
assert(exception_thrown);
// Since the operation was not performed, the tables should be unaltered.
assert(h2.size() == 2);
assert(h3[2] == 'b');
return 0;
}
|
