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
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
|
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#include <sal/config.h>
#include <string_view>
#include <editeng/Trie.hxx>
namespace editeng
{
/* TrieNode */
struct TrieNode final
{
static const int LATIN_ARRAY_SIZE = 26;
sal_Unicode mCharacter;
bool mMarker;
std::vector<std::unique_ptr<TrieNode>> mChildren;
std::unique_ptr<TrieNode> mLatinArray[LATIN_ARRAY_SIZE];
explicit TrieNode(sal_Unicode aCharacter = '\0');
void markWord();
TrieNode* findChild(sal_Unicode aCharacter);
TrieNode* traversePath(std::u16string_view sPath);
void addNewChild(TrieNode* pChild);
void collectSuggestions(std::u16string_view sPath, std::vector<OUString>& rSuggestionList);
static void collectSuggestionsForCurrentNode(TrieNode* pCurrent, std::u16string_view sPath, std::vector<OUString>& rSuggestionList);
};
TrieNode::TrieNode(sal_Unicode aCharacter) :
mCharacter(aCharacter),
mMarker(false)
{
for (auto & i : mLatinArray)
{
i = nullptr;
}
}
void TrieNode::markWord()
{
mMarker = true;
}
void TrieNode::addNewChild(TrieNode* pChild)
{
if (pChild->mCharacter >= 'a' &&
pChild->mCharacter <= 'z')
{
mLatinArray[pChild->mCharacter - u'a'].reset(pChild);
}
else
{
mChildren.push_back(std::unique_ptr<TrieNode>(pChild));
}
}
TrieNode* TrieNode::findChild(sal_Unicode aInputCharacter)
{
if (aInputCharacter >= 'a' &&
aInputCharacter <= 'z')
{
return mLatinArray[aInputCharacter - u'a'].get();
}
for(auto const & pCurrent : mChildren)
{
if ( pCurrent->mCharacter == aInputCharacter )
return pCurrent.get();
}
return nullptr;
}
void TrieNode::collectSuggestions(std::u16string_view sPath, std::vector<OUString>& rSuggestionList)
{
// first traverse nodes for alphabet characters
for (auto const & pCurrent : mLatinArray)
{
if (pCurrent != nullptr)
collectSuggestionsForCurrentNode(pCurrent.get(), sPath, rSuggestionList);
}
// traverse nodes for other characters
for(auto const & pCurrent : mChildren)
{
if (pCurrent != nullptr)
collectSuggestionsForCurrentNode(pCurrent.get(), sPath, rSuggestionList);
}
}
void TrieNode::collectSuggestionsForCurrentNode(TrieNode* pCurrent, std::u16string_view sPath, std::vector<OUString>& rSuggestionList)
{
OUString aStringPath = sPath + OUStringChar(pCurrent->mCharacter);
if(pCurrent->mMarker)
{
rSuggestionList.push_back(aStringPath);
}
// recursively descend tree
pCurrent->collectSuggestions(aStringPath, rSuggestionList);
}
TrieNode* TrieNode::traversePath(std::u16string_view sPath)
{
TrieNode* pCurrent = this;
for ( const auto aCurrentChar : sPath )
{
pCurrent = pCurrent->findChild(aCurrentChar);
if ( pCurrent == nullptr )
return nullptr;
}
return pCurrent;
}
/* TRIE */
Trie::Trie() :
mRoot(new TrieNode())
{}
Trie::~Trie()
{}
void Trie::insert(std::u16string_view sInputString) const
{
// adding an empty word is not allowed
if ( sInputString.empty() )
{
return;
}
// traverse the input string and modify the tree with new nodes / characters
TrieNode* pCurrent = mRoot.get();
for ( const auto aCurrentChar : sInputString )
{
TrieNode* pChild = pCurrent->findChild(aCurrentChar);
if ( pChild == nullptr )
{
TrieNode* pNewNode = new TrieNode(aCurrentChar);
pCurrent->addNewChild(pNewNode);
pCurrent = pNewNode;
}
else
{
pCurrent = pChild;
}
}
pCurrent->markWord();
}
void Trie::findSuggestions(std::u16string_view sWordPart, std::vector<OUString>& rSuggestionList) const
{
TrieNode* pNode = mRoot->traversePath(sWordPart);
if (pNode != nullptr)
{
pNode->collectSuggestions(sWordPart, rSuggestionList);
}
}
size_t Trie::size() const
{
if (!mRoot)
return 0;
std::vector<OUString> entries;
mRoot->collectSuggestions(std::u16string_view(), entries);
return entries.size();
}
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
|
