1 | #ifndef _theplu_svndigest_vector_ |
---|
2 | #define _theplu_svndigest_vector_ |
---|
3 | |
---|
4 | // $Id: Vector.h 1194 2010-10-03 23:39:12Z peter $ |
---|
5 | |
---|
6 | /* |
---|
7 | Copyright (C) 2010 Peter Johansson |
---|
8 | |
---|
9 | This file is part of svndigest, http://dev.thep.lu.se/svndigest |
---|
10 | |
---|
11 | svndigest is free software; you can redistribute it and/or modify it |
---|
12 | under the terms of the GNU General Public License as published by |
---|
13 | the Free Software Foundation; either version 3 of the License, or |
---|
14 | (at your option) any later version. |
---|
15 | |
---|
16 | svndigest is distributed in the hope that it will be useful, but |
---|
17 | WITHOUT ANY WARRANTY; without even the implied warranty of |
---|
18 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
---|
19 | General Public License for more details. |
---|
20 | |
---|
21 | You should have received a copy of the GNU General Public License |
---|
22 | along with svndigest. If not, see <http://www.gnu.org/licenses/>. |
---|
23 | */ |
---|
24 | |
---|
25 | #include <iostream> |
---|
26 | |
---|
27 | #include <subversion-1/svn_types.h> |
---|
28 | |
---|
29 | #include <algorithm> |
---|
30 | #include <cassert> |
---|
31 | #include <map> |
---|
32 | |
---|
33 | namespace theplu { |
---|
34 | namespace svndigest { |
---|
35 | |
---|
36 | /** |
---|
37 | \brief Sparse Vector |
---|
38 | */ |
---|
39 | template<typename T, class Policy> |
---|
40 | class Vector { |
---|
41 | typedef typename std::map<svn_revnum_t, T> Map; |
---|
42 | public: |
---|
43 | // iterator to underlying container, used in begin() and end() |
---|
44 | typedef typename Map::const_iterator const_iterator; |
---|
45 | // iterator to underlying container, used in begin() and end() |
---|
46 | typedef typename Map::const_reverse_iterator const_reverse_iterator; |
---|
47 | |
---|
48 | /** |
---|
49 | \brief default constructor |
---|
50 | */ |
---|
51 | Vector(void) |
---|
52 | : size_(0) |
---|
53 | {} |
---|
54 | |
---|
55 | /** |
---|
56 | \note Vector cannot be empty |
---|
57 | |
---|
58 | \return last element |
---|
59 | */ |
---|
60 | T back(void) const |
---|
61 | { |
---|
62 | // FIXME: avoid logN lookup time |
---|
63 | assert(size()>0); |
---|
64 | return (*this)[size()-1]; |
---|
65 | } |
---|
66 | |
---|
67 | /** |
---|
68 | \return first non-trivial element |
---|
69 | |
---|
70 | The iterator iterates only over non-trivial element, e.g., |
---|
71 | non-zero in SparseVector. If you need to iterate over all |
---|
72 | elements you can use operator[] and size(). |
---|
73 | */ |
---|
74 | const_iterator begin(void) const { return map_.begin(); } |
---|
75 | |
---|
76 | /** |
---|
77 | \brief make container empty |
---|
78 | */ |
---|
79 | void clear(void) |
---|
80 | { |
---|
81 | map_.clear(); |
---|
82 | size_ = 0; |
---|
83 | } |
---|
84 | |
---|
85 | /** |
---|
86 | \return true if Vector is empty |
---|
87 | */ |
---|
88 | bool empty(void) const |
---|
89 | { return map_.empty(); } |
---|
90 | |
---|
91 | /* |
---|
92 | \return end of Vector |
---|
93 | */ |
---|
94 | const_iterator end(void) const { return map_.end(); } |
---|
95 | |
---|
96 | /** |
---|
97 | same as begin() but reverse iterator |
---|
98 | */ |
---|
99 | const_reverse_iterator rbegin(void) const { return map_.rbegin(); } |
---|
100 | |
---|
101 | /** |
---|
102 | same as end() but reverse iterator |
---|
103 | */ |
---|
104 | const_reverse_iterator rend(void) const { return map_.rend(); } |
---|
105 | |
---|
106 | /* |
---|
107 | set size to \a size |
---|
108 | */ |
---|
109 | void resize(svn_revnum_t size) |
---|
110 | { |
---|
111 | size_ = size; |
---|
112 | } |
---|
113 | |
---|
114 | /** |
---|
115 | works as vec[revision] = count |
---|
116 | */ |
---|
117 | void set(svn_revnum_t revision, T count) |
---|
118 | { |
---|
119 | // FIXME: we should let policy collaps map, if possible |
---|
120 | map_[revision] = count; |
---|
121 | size_ = std::max(revision+1, size_); |
---|
122 | } |
---|
123 | |
---|
124 | /** |
---|
125 | \return value of revision \a rev |
---|
126 | |
---|
127 | If revision \a rev is non-trivial, i.e., directly stored in |
---|
128 | underlying container, its value is returned. Otherwise, return |
---|
129 | value is decided by the policy class. |
---|
130 | */ |
---|
131 | T operator[](svn_revnum_t rev) const |
---|
132 | { |
---|
133 | const_iterator i = map_.lower_bound(rev); |
---|
134 | if (i!=map_.end() && i->first == rev) |
---|
135 | return i->second; |
---|
136 | return policy_.get(map_, i); |
---|
137 | } |
---|
138 | |
---|
139 | /** |
---|
140 | \brief add \a other to this |
---|
141 | */ |
---|
142 | Vector& operator+=(const Vector& other) |
---|
143 | { |
---|
144 | Vector result; |
---|
145 | typename Map::iterator first1 = map_.begin(); |
---|
146 | typename Map::iterator last1 = map_.end(); |
---|
147 | const_iterator first2 = other.begin(); |
---|
148 | const_iterator last2 = other.end(); |
---|
149 | while (first1!=last1 || first2!=last2) { |
---|
150 | svn_revnum_t rev = 0; |
---|
151 | if (first1==last1) { |
---|
152 | rev = first2->first; |
---|
153 | ++first2; |
---|
154 | } |
---|
155 | else if (first2==last2) { |
---|
156 | rev = first1->first; |
---|
157 | ++first1; |
---|
158 | } |
---|
159 | else if (first1->first < first2->first) { |
---|
160 | rev = first1->first; |
---|
161 | ++first1; |
---|
162 | } |
---|
163 | else if (first1->first == first2->first) { |
---|
164 | rev = first1->first; |
---|
165 | ++first1; |
---|
166 | ++first2; |
---|
167 | } |
---|
168 | else if (first1->first > first2->first) { |
---|
169 | rev = first2->first; |
---|
170 | ++first2; |
---|
171 | } |
---|
172 | result.set(rev, (*this)[rev] + other[rev]); |
---|
173 | } |
---|
174 | // assign result map to this |
---|
175 | std::swap(map_, result.map_); |
---|
176 | resize(std::max(size_, other.size())); |
---|
177 | } |
---|
178 | |
---|
179 | /** |
---|
180 | \return size of vector |
---|
181 | */ |
---|
182 | svn_revnum_t size(void) const |
---|
183 | { |
---|
184 | return size_; |
---|
185 | } |
---|
186 | |
---|
187 | private: |
---|
188 | Map map_; |
---|
189 | Policy policy_; |
---|
190 | svn_revnum_t size_; |
---|
191 | |
---|
192 | // using compiler generated copy constructor |
---|
193 | // Vector(const Vector&) |
---|
194 | // Vector& operator=(const Vector&); |
---|
195 | }; |
---|
196 | |
---|
197 | template<typename T, class Policy> |
---|
198 | Vector<T, Policy> operator+(const Vector<T, Policy>& lhs, |
---|
199 | const Vector<T, Policy>& rhs) |
---|
200 | { |
---|
201 | Vector<T, Policy> result(lhs); |
---|
202 | result+=rhs; |
---|
203 | assert(result.size()>=lhs.size()); |
---|
204 | assert(result.size()>=rhs.size()); |
---|
205 | return result; |
---|
206 | } |
---|
207 | |
---|
208 | |
---|
209 | template<typename T> |
---|
210 | class SparsePolicy |
---|
211 | { |
---|
212 | typedef typename std::map<svn_revnum_t, T> M; |
---|
213 | public: |
---|
214 | T get(const M&, typename M::const_iterator) const |
---|
215 | { return 0; } |
---|
216 | |
---|
217 | }; |
---|
218 | |
---|
219 | typedef Vector<unsigned int, SparsePolicy<unsigned int> > SparseVector; |
---|
220 | |
---|
221 | template<typename T> |
---|
222 | class SumPolicy |
---|
223 | { |
---|
224 | typedef typename std::map<svn_revnum_t, T> M; |
---|
225 | public: |
---|
226 | /* |
---|
227 | iter points to first element after rev, while we wanna return |
---|
228 | the value of the first element before rev, so we iterate one |
---|
229 | step back and return its value; |
---|
230 | |
---|
231 | The exception is when there is no value before rev in which case |
---|
232 | we return 0, i.e., all revs up to the first element is 0. |
---|
233 | */ |
---|
234 | T get(const M& map, typename M::const_iterator iter) const |
---|
235 | { |
---|
236 | if (iter==map.begin()) |
---|
237 | return 0; |
---|
238 | return (--iter)->second; |
---|
239 | } |
---|
240 | }; |
---|
241 | |
---|
242 | typedef Vector<unsigned int, SumPolicy<unsigned int> > SumVector; |
---|
243 | |
---|
244 | /** |
---|
245 | create a SumVector from a ParseVector |
---|
246 | |
---|
247 | result[i] = result[i-1] + vec[i]; |
---|
248 | */ |
---|
249 | void accumulate(const SparseVector& vec, SumVector& result); |
---|
250 | |
---|
251 | }} // end of namespace svndigest and namespace theplu |
---|
252 | |
---|
253 | #endif |
---|