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
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
|
// unordered_map implementation -*- C++ -*-
// Copyright (C) 2010-2013 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.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file bits/unordered_map.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{unordered_map}
*/
#ifndef _UNORDERED_MAP_H
#define _UNORDERED_MAP_H
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_CONTAINER
/// Base types for unordered_map.
template<bool _Cache>
using __umap_traits = __detail::_Hashtable_traits<_Cache, false, true>;
template<typename _Key,
typename _Tp,
typename _Hash = hash<_Key>,
typename _Pred = std::equal_to<_Key>,
typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >,
typename _Tr = __umap_traits<__cache_default<_Key, _Hash>::value>>
using __umap_hashtable = _Hashtable<_Key, std::pair<const _Key, _Tp>,
_Alloc, __detail::_Select1st,
_Pred, _Hash,
__detail::_Mod_range_hashing,
__detail::_Default_ranged_hash,
__detail::_Prime_rehash_policy, _Tr>;
/// Base types for unordered_multimap.
template<bool _Cache>
using __ummap_traits = __detail::_Hashtable_traits<_Cache, false, false>;
template<typename _Key,
typename _Tp,
typename _Hash = hash<_Key>,
typename _Pred = std::equal_to<_Key>,
typename _Alloc = std::allocator<std::pair<const _Key, _Tp> >,
typename _Tr = __ummap_traits<__cache_default<_Key, _Hash>::value>>
using __ummap_hashtable = _Hashtable<_Key, std::pair<const _Key, _Tp>,
_Alloc, __detail::_Select1st,
_Pred, _Hash,
__detail::_Mod_range_hashing,
__detail::_Default_ranged_hash,
__detail::_Prime_rehash_policy, _Tr>;
/**
* @brief A standard container composed of unique keys (containing
* at most one of each key value) that associates values of another type
* with the keys.
*
* @ingroup unordered_associative_containers
*
* @tparam _Key Type of key objects.
* @tparam _Tp Type of mapped objects.
* @tparam _Hash Hashing function object type, defaults to hash<_Value>.
* @tparam _Pred Predicate function object type, defaults
* to equal_to<_Value>.
* @tparam _Alloc Allocator type, defaults to allocator<_Key>.
*
* Meets the requirements of a <a href="tables.html#65">container</a>, and
* <a href="tables.html#xx">unordered associative container</a>
*
* The resulting value type of the container is std::pair<const _Key, _Tp>.
*
* Base is _Hashtable, dispatched at compile time via template
* alias __umap_hashtable.
*/
template<class _Key, class _Tp,
class _Hash = hash<_Key>,
class _Pred = std::equal_to<_Key>,
class _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
class unordered_map
{
typedef __umap_hashtable<_Key, _Tp, _Hash, _Pred, _Alloc> _Hashtable;
_Hashtable _M_h;
public:
// typedefs:
//@{
/// Public typedefs.
typedef typename _Hashtable::key_type key_type;
typedef typename _Hashtable::value_type value_type;
typedef typename _Hashtable::mapped_type mapped_type;
typedef typename _Hashtable::hasher hasher;
typedef typename _Hashtable::key_equal key_equal;
typedef typename _Hashtable::allocator_type allocator_type;
//@}
//@{
/// Iterator-related typedefs.
typedef typename allocator_type::pointer pointer;
typedef typename allocator_type::const_pointer const_pointer;
typedef typename allocator_type::reference reference;
typedef typename allocator_type::const_reference const_reference;
typedef typename _Hashtable::iterator iterator;
typedef typename _Hashtable::const_iterator const_iterator;
typedef typename _Hashtable::local_iterator local_iterator;
typedef typename _Hashtable::const_local_iterator const_local_iterator;
typedef typename _Hashtable::size_type size_type;
typedef typename _Hashtable::difference_type difference_type;
//@}
//construct/destroy/copy
/**
* @brief Default constructor creates no elements.
* @param __n Initial number of buckets.
* @param __hf A hash functor.
* @param __eql A key equality functor.
* @param __a An allocator object.
*/
explicit
unordered_map(size_type __n = 10,
const hasher& __hf = hasher(),
const key_equal& __eql = key_equal(),
const allocator_type& __a = allocator_type())
: _M_h(__n, __hf, __eql, __a)
{ }
/**
* @brief Builds an %unordered_map from a range.
* @param __first An input iterator.
* @param __last An input iterator.
* @param __n Minimal initial number of buckets.
* @param __hf A hash functor.
* @param __eql A key equality functor.
* @param __a An allocator object.
*
* Create an %unordered_map consisting of copies of the elements from
* [__first,__last). This is linear in N (where N is
* distance(__first,__last)).
*/
template<typename _InputIterator>
unordered_map(_InputIterator __f, _InputIterator __l,
size_type __n = 0,
const hasher& __hf = hasher(),
const key_equal& __eql = key_equal(),
const allocator_type& __a = allocator_type())
: _M_h(__f, __l, __n, __hf, __eql, __a)
{ }
/// Copy constructor.
unordered_map(const unordered_map&) = default;
/// Move constructor.
unordered_map(unordered_map&&) = default;
/**
* @brief Builds an %unordered_map from an initializer_list.
* @param __l An initializer_list.
* @param __n Minimal initial number of buckets.
* @param __hf A hash functor.
* @param __eql A key equality functor.
* @param __a An allocator object.
*
* Create an %unordered_map consisting of copies of the elements in the
* list. This is linear in N (where N is @a __l.size()).
*/
unordered_map(initializer_list<value_type> __l,
size_type __n = 0,
const hasher& __hf = hasher(),
const key_equal& __eql = key_equal(),
const allocator_type& __a = allocator_type())
: _M_h(__l, __n, __hf, __eql, __a)
{ }
/// Copy assignment operator.
unordered_map&
operator=(const unordered_map&) = default;
/// Move assignment operator.
unordered_map&
operator=(unordered_map&&) = default;
/**
* @brief %Unordered_map list assignment operator.
* @param __l An initializer_list.
*
* This function fills an %unordered_map with copies of the elements in
* the initializer list @a __l.
*
* Note that the assignment completely changes the %unordered_map and
* that the resulting %unordered_map's size is the same as the number
* of elements assigned. Old data may be lost.
*/
unordered_map&
operator=(initializer_list<value_type> __l)
{
_M_h = __l;
return *this;
}
/// Returns the allocator object with which the %unordered_map was
/// constructed.
allocator_type
get_allocator() const noexcept
{ return _M_h.get_allocator(); }
// size and capacity:
/// Returns true if the %unordered_map is empty.
bool
empty() const noexcept
{ return _M_h.empty(); }
/// Returns the size of the %unordered_map.
size_type
size() const noexcept
{ return _M_h.size(); }
/// Returns the maximum size of the %unordered_map.
size_type
max_size() const noexcept
{ return _M_h.max_size(); }
// iterators.
/**
* Returns a read/write iterator that points to the first element in the
* %unordered_map.
*/
iterator
begin() noexcept
{ return _M_h.begin(); }
//@{
/**
* Returns a read-only (constant) iterator that points to the first
* element in the %unordered_map.
*/
const_iterator
begin() const noexcept
{ return _M_h.begin(); }
const_iterator
cbegin() const noexcept
{ return _M_h.begin(); }
//@}
/**
* Returns a read/write iterator that points one past the last element in
* the %unordered_map.
*/
iterator
end() noexcept
{ return _M_h.end(); }
//@{
/**
* Returns a read-only (constant) iterator that points one past the last
* element in the %unordered_map.
*/
const_iterator
end() const noexcept
{ return _M_h.end(); }
const_iterator
cend() const noexcept
{ return _M_h.end(); }
//@}
// modifiers.
/**
* @brief Attempts to build and insert a std::pair into the %unordered_map.
*
* @param __args Arguments used to generate a new pair instance (see
* std::piecewise_contruct for passing arguments to each
* part of the pair constructor).
*
* @return A pair, of which the first element is an iterator that points
* to the possibly inserted pair, and the second is a bool that
* is true if the pair was actually inserted.
*
* This function attempts to build and insert a (key, value) %pair into
* the %unordered_map.
* An %unordered_map relies on unique keys and thus a %pair is only
* inserted if its first element (the key) is not already present in the
* %unordered_map.
*
* Insertion requires amortized constant time.
*/
template<typename... _Args>
std::pair<iterator, bool>
emplace(_Args&&... __args)
{ return _M_h.emplace(std::forward<_Args>(__args)...); }
/**
* @brief Attempts to build and insert a std::pair into the %unordered_map.
*
* @param __pos An iterator that serves as a hint as to where the pair
* should be inserted.
* @param __args Arguments used to generate a new pair instance (see
* std::piecewise_contruct for passing arguments to each
* part of the pair constructor).
* @return An iterator that points to the element with key of the
* std::pair built from @a __args (may or may not be that
* std::pair).
*
* This function is not concerned about whether the insertion took place,
* and thus does not return a boolean like the single-argument emplace()
* does.
* Note that the first parameter is only a hint and can potentially
* improve the performance of the insertion process. A bad hint would
* cause no gains in efficiency.
*
* See
* http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
* for more on @a hinting.
*
* Insertion requires amortized constant time.
*/
template<typename... _Args>
iterator
emplace_hint(const_iterator __pos, _Args&&... __args)
{ return _M_h.emplace_hint(__pos, std::forward<_Args>(__args)...); }
//@{
/**
* @brief Attempts to insert a std::pair into the %unordered_map.
* @param __x Pair to be inserted (see std::make_pair for easy
* creation of pairs).
*
* @return A pair, of which the first element is an iterator that
* points to the possibly inserted pair, and the second is
* a bool that is true if the pair was actually inserted.
*
* This function attempts to insert a (key, value) %pair into the
* %unordered_map. An %unordered_map relies on unique keys and thus a
* %pair is only inserted if its first element (the key) is not already
* present in the %unordered_map.
*
* Insertion requires amortized constant time.
*/
std::pair<iterator, bool>
insert(const value_type& __x)
{ return _M_h.insert(__x); }
template<typename _Pair, typename = typename
std::enable_if<std::is_constructible<value_type,
_Pair&&>::value>::type>
std::pair<iterator, bool>
insert(_Pair&& __x)
{ return _M_h.insert(std::move(__x)); }
//@}
//@{
/**
* @brief Attempts to insert a std::pair into the %unordered_map.
* @param __hint An iterator that serves as a hint as to where the
* pair should be inserted.
* @param __x Pair to be inserted (see std::make_pair for easy creation
* of pairs).
* @return An iterator that points to the element with key of
* @a __x (may or may not be the %pair passed in).
*
* This function is not concerned about whether the insertion took place,
* and thus does not return a boolean like the single-argument insert()
* does. Note that the first parameter is only a hint and can
* potentially improve the performance of the insertion process. A bad
* hint would cause no gains in efficiency.
*
* See
* http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
* for more on @a hinting.
*
* Insertion requires amortized constant time.
*/
iterator
insert(const_iterator __hint, const value_type& __x)
{ return _M_h.insert(__hint, __x); }
template<typename _Pair, typename = typename
std::enable_if<std::is_constructible<value_type,
_Pair&&>::value>::type>
iterator
insert(const_iterator __hint, _Pair&& __x)
{ return _M_h.insert(__hint, std::move(__x)); }
//@}
/**
* @brief A template function that attempts to insert a range of
* elements.
* @param __first Iterator pointing to the start of the range to be
* inserted.
* @param __last Iterator pointing to the end of the range.
*
* Complexity similar to that of the range constructor.
*/
template<typename _InputIterator>
void
insert(_InputIterator __first, _InputIterator __last)
{ _M_h.insert(__first, __last); }
/**
* @brief Attempts to insert a list of elements into the %unordered_map.
* @param __l A std::initializer_list<value_type> of elements
* to be inserted.
*
* Complexity similar to that of the range constructor.
*/
void
insert(initializer_list<value_type> __l)
{ _M_h.insert(__l); }
//@{
/**
* @brief Erases an element from an %unordered_map.
* @param __position An iterator pointing to the element to be erased.
* @return An iterator pointing to the element immediately following
* @a __position prior to the element being erased. If no such
* element exists, end() is returned.
*
* This function erases an element, pointed to by the given iterator,
* from an %unordered_map.
* Note that this function only erases the element, and that if the
* element is itself a pointer, the pointed-to memory is not touched in
* any way. Managing the pointer is the user's responsibility.
*/
iterator
erase(const_iterator __position)
{ return _M_h.erase(__position); }
// LWG 2059.
iterator
erase(iterator __it)
{ return _M_h.erase(__it); }
//@}
/**
* @brief Erases elements according to the provided key.
* @param __x Key of element to be erased.
* @return The number of elements erased.
*
* This function erases all the elements located by the given key from
* an %unordered_map. For an %unordered_map the result of this function
* can only be 0 (not present) or 1 (present).
* Note that this function only erases the element, and that if the
* element is itself a pointer, the pointed-to memory is not touched in
* any way. Managing the pointer is the user's responsibility.
*/
size_type
erase(const key_type& __x)
{ return _M_h.erase(__x); }
/**
* @brief Erases a [__first,__last) range of elements from an
* %unordered_map.
* @param __first Iterator pointing to the start of the range to be
* erased.
* @param __last Iterator pointing to the end of the range to
* be erased.
* @return The iterator @a __last.
*
* This function erases a sequence of elements from an %unordered_map.
* Note that this function only erases the elements, and that if
* the element is itself a pointer, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibility.
*/
iterator
erase(const_iterator __first, const_iterator __last)
{ return _M_h.erase(__first, __last); }
/**
* Erases all elements in an %unordered_map.
* Note that this function only erases the elements, and that if the
* elements themselves are pointers, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibility.
*/
void
clear() noexcept
{ _M_h.clear(); }
/**
* @brief Swaps data with another %unordered_map.
* @param __x An %unordered_map of the same element and allocator
* types.
*
* This exchanges the elements between two %unordered_map in constant time.
* Note that the global std::swap() function is specialized such that
* std::swap(m1,m2) will feed to this function.
*/
void
swap(unordered_map& __x)
{ _M_h.swap(__x._M_h); }
// observers.
/// Returns the hash functor object with which the %unordered_map was
/// constructed.
hasher
hash_function() const
{ return _M_h.hash_function(); }
/// Returns the key comparison object with which the %unordered_map was
/// constructed.
key_equal
key_eq() const
{ return _M_h.key_eq(); }
// lookup.
//@{
/**
* @brief Tries to locate an element in an %unordered_map.
* @param __x Key to be located.
* @return Iterator pointing to sought-after element, or end() if not
* found.
*
* This function takes a key and tries to locate the element with which
* the key matches. If successful the function returns an iterator
* pointing to the sought after element. If unsuccessful it returns the
* past-the-end ( @c end() ) iterator.
*/
iterator
find(const key_type& __x)
{ return _M_h.find(__x); }
const_iterator
find(const key_type& __x) const
{ return _M_h.find(__x); }
//@}
/**
* @brief Finds the number of elements.
* @param __x Key to count.
* @return Number of elements with specified key.
*
* This function only makes sense for %unordered_multimap; for
* %unordered_map the result will either be 0 (not present) or 1
* (present).
*/
size_type
count(const key_type& __x) const
{ return _M_h.count(__x); }
//@{
/**
* @brief Finds a subsequence matching given key.
* @param __x Key to be located.
* @return Pair of iterators that possibly points to the subsequence
* matching given key.
*
* This function probably only makes sense for %unordered_multimap.
*/
std::pair<iterator, iterator>
equal_range(const key_type& __x)
{ return _M_h.equal_range(__x); }
std::pair<const_iterator, const_iterator>
equal_range(const key_type& __x) const
{ return _M_h.equal_range(__x); }
//@}
//@{
/**
* @brief Subscript ( @c [] ) access to %unordered_map data.
* @param __k The key for which data should be retrieved.
* @return A reference to the data of the (key,data) %pair.
*
* Allows for easy lookup with the subscript ( @c [] )operator. Returns
* data associated with the key specified in subscript. If the key does
* not exist, a pair with that key is created using default values, which
* is then returned.
*
* Lookup requires constant time.
*/
mapped_type&
operator[](const key_type& __k)
{ return _M_h[__k]; }
mapped_type&
operator[](key_type&& __k)
{ return _M_h[std::move(__k)]; }
//@}
//@{
/**
* @brief Access to %unordered_map data.
* @param __k The key for which data should be retrieved.
* @return A reference to the data whose key is equal to @a __k, if
* such a data is present in the %unordered_map.
* @throw std::out_of_range If no such data is present.
*/
mapped_type&
at(const key_type& __k)
{ return _M_h.at(__k); }
const mapped_type&
at(const key_type& __k) const
{ return _M_h.at(__k); }
//@}
// bucket interface.
/// Returns the number of buckets of the %unordered_map.
size_type
bucket_count() const noexcept
{ return _M_h.bucket_count(); }
/// Returns the maximum number of buckets of the %unordered_map.
size_type
max_bucket_count() const noexcept
{ return _M_h.max_bucket_count(); }
/*
* @brief Returns the number of elements in a given bucket.
* @param __n A bucket index.
* @return The number of elements in the bucket.
*/
size_type
bucket_size(size_type __n) const
{ return _M_h.bucket_size(__n); }
/*
* @brief Returns the bucket index of a given element.
* @param __key A key instance.
* @return The key bucket index.
*/
size_type
bucket(const key_type& __key) const
{ return _M_h.bucket(__key); }
/**
* @brief Returns a read/write iterator pointing to the first bucket
* element.
* @param __n The bucket index.
* @return A read/write local iterator.
*/
local_iterator
begin(size_type __n)
{ return _M_h.begin(__n); }
//@{
/**
* @brief Returns a read-only (constant) iterator pointing to the first
* bucket element.
* @param __n The bucket index.
* @return A read-only local iterator.
*/
const_local_iterator
begin(size_type __n) const
{ return _M_h.begin(__n); }
const_local_iterator
cbegin(size_type __n) const
{ return _M_h.cbegin(__n); }
//@}
/**
* @brief Returns a read/write iterator pointing to one past the last
* bucket elements.
* @param __n The bucket index.
* @return A read/write local iterator.
*/
local_iterator
end(size_type __n)
{ return _M_h.end(__n); }
//@{
/**
* @brief Returns a read-only (constant) iterator pointing to one past
* the last bucket elements.
* @param __n The bucket index.
* @return A read-only local iterator.
*/
const_local_iterator
end(size_type __n) const
{ return _M_h.end(__n); }
const_local_iterator
cend(size_type __n) const
{ return _M_h.cend(__n); }
//@}
// hash policy.
/// Returns the average number of elements per bucket.
float
load_factor() const noexcept
{ return _M_h.load_factor(); }
/// Returns a positive number that the %unordered_map tries to keep the
/// load factor less than or equal to.
float
max_load_factor() const noexcept
{ return _M_h.max_load_factor(); }
/**
* @brief Change the %unordered_map maximum load factor.
* @param __z The new maximum load factor.
*/
void
max_load_factor(float __z)
{ _M_h.max_load_factor(__z); }
/**
* @brief May rehash the %unordered_map.
* @param __n The new number of buckets.
*
* Rehash will occur only if the new number of buckets respect the
* %unordered_map maximum load factor.
*/
void
rehash(size_type __n)
{ _M_h.rehash(__n); }
/**
* @brief Prepare the %unordered_map for a specified number of
* elements.
* @param __n Number of elements required.
*
* Same as rehash(ceil(n / max_load_factor())).
*/
void
reserve(size_type __n)
{ _M_h.reserve(__n); }
template<typename _Key1, typename _Tp1, typename _Hash1, typename _Pred1,
typename _Alloc1>
friend bool
operator==(const unordered_map<_Key1, _Tp1, _Hash1, _Pred1, _Alloc1>&,
const unordered_map<_Key1, _Tp1, _Hash1, _Pred1, _Alloc1>&);
};
/**
* @brief A standard container composed of equivalent keys
* (possibly containing multiple of each key value) that associates
* values of another type with the keys.
*
* @ingroup unordered_associative_containers
*
* @tparam _Key Type of key objects.
* @tparam _Tp Type of mapped objects.
* @tparam _Hash Hashing function object type, defaults to hash<_Value>.
* @tparam _Pred Predicate function object type, defaults
* to equal_to<_Value>.
* @tparam _Alloc Allocator type, defaults to allocator<_Key>.
*
* Meets the requirements of a <a href="tables.html#65">container</a>, and
* <a href="tables.html#xx">unordered associative container</a>
*
* The resulting value type of the container is std::pair<const _Key, _Tp>.
*
* Base is _Hashtable, dispatched at compile time via template
* alias __ummap_hashtable.
*/
template<class _Key, class _Tp,
class _Hash = hash<_Key>,
class _Pred = std::equal_to<_Key>,
class _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
class unordered_multimap
{
typedef __ummap_hashtable<_Key, _Tp, _Hash, _Pred, _Alloc> _Hashtable;
_Hashtable _M_h;
public:
// typedefs:
//@{
/// Public typedefs.
typedef typename _Hashtable::key_type key_type;
typedef typename _Hashtable::value_type value_type;
typedef typename _Hashtable::mapped_type mapped_type;
typedef typename _Hashtable::hasher hasher;
typedef typename _Hashtable::key_equal key_equal;
typedef typename _Hashtable::allocator_type allocator_type;
//@}
//@{
/// Iterator-related typedefs.
typedef typename allocator_type::pointer pointer;
typedef typename allocator_type::const_pointer const_pointer;
typedef typename allocator_type::reference reference;
typedef typename allocator_type::const_reference const_reference;
typedef typename _Hashtable::iterator iterator;
typedef typename _Hashtable::const_iterator const_iterator;
typedef typename _Hashtable::local_iterator local_iterator;
typedef typename _Hashtable::const_local_iterator const_local_iterator;
typedef typename _Hashtable::size_type size_type;
typedef typename _Hashtable::difference_type difference_type;
//@}
//construct/destroy/copy
/**
* @brief Default constructor creates no elements.
* @param __n Initial number of buckets.
* @param __hf A hash functor.
* @param __eql A key equality functor.
* @param __a An allocator object.
*/
explicit
unordered_multimap(size_type __n = 10,
const hasher& __hf = hasher(),
const key_equal& __eql = key_equal(),
const allocator_type& __a = allocator_type())
: _M_h(__n, __hf, __eql, __a)
{ }
/**
* @brief Builds an %unordered_multimap from a range.
* @param __first An input iterator.
* @param __last An input iterator.
* @param __n Minimal initial number of buckets.
* @param __hf A hash functor.
* @param __eql A key equality functor.
* @param __a An allocator object.
*
* Create an %unordered_multimap consisting of copies of the elements
* from [__first,__last). This is linear in N (where N is
* distance(__first,__last)).
*/
template<typename _InputIterator>
unordered_multimap(_InputIterator __f, _InputIterator __l,
size_type __n = 0,
const hasher& __hf = hasher(),
const key_equal& __eql = key_equal(),
const allocator_type& __a = allocator_type())
: _M_h(__f, __l, __n, __hf, __eql, __a)
{ }
/// Copy constructor.
unordered_multimap(const unordered_multimap&) = default;
/// Move constructor.
unordered_multimap(unordered_multimap&&) = default;
/**
* @brief Builds an %unordered_multimap from an initializer_list.
* @param __l An initializer_list.
* @param __n Minimal initial number of buckets.
* @param __hf A hash functor.
* @param __eql A key equality functor.
* @param __a An allocator object.
*
* Create an %unordered_multimap consisting of copies of the elements in
* the list. This is linear in N (where N is @a __l.size()).
*/
unordered_multimap(initializer_list<value_type> __l,
size_type __n = 0,
const hasher& __hf = hasher(),
const key_equal& __eql = key_equal(),
const allocator_type& __a = allocator_type())
: _M_h(__l, __n, __hf, __eql, __a)
{ }
/// Copy assignment operator.
unordered_multimap&
operator=(const unordered_multimap&) = default;
/// Move assignment operator.
unordered_multimap&
operator=(unordered_multimap&&) = default;
/**
* @brief %Unordered_multimap list assignment operator.
* @param __l An initializer_list.
*
* This function fills an %unordered_multimap with copies of the elements
* in the initializer list @a __l.
*
* Note that the assignment completely changes the %unordered_multimap
* and that the resulting %unordered_multimap's size is the same as the
* number of elements assigned. Old data may be lost.
*/
unordered_multimap&
operator=(initializer_list<value_type> __l)
{
_M_h = __l;
return *this;
}
/// Returns the allocator object with which the %unordered_multimap was
/// constructed.
allocator_type
get_allocator() const noexcept
{ return _M_h.get_allocator(); }
// size and capacity:
/// Returns true if the %unordered_multimap is empty.
bool
empty() const noexcept
{ return _M_h.empty(); }
/// Returns the size of the %unordered_multimap.
size_type
size() const noexcept
{ return _M_h.size(); }
/// Returns the maximum size of the %unordered_multimap.
size_type
max_size() const noexcept
{ return _M_h.max_size(); }
// iterators.
/**
* Returns a read/write iterator that points to the first element in the
* %unordered_multimap.
*/
iterator
begin() noexcept
{ return _M_h.begin(); }
//@{
/**
* Returns a read-only (constant) iterator that points to the first
* element in the %unordered_multimap.
*/
const_iterator
begin() const noexcept
{ return _M_h.begin(); }
const_iterator
cbegin() const noexcept
{ return _M_h.begin(); }
//@}
/**
* Returns a read/write iterator that points one past the last element in
* the %unordered_multimap.
*/
iterator
end() noexcept
{ return _M_h.end(); }
//@{
/**
* Returns a read-only (constant) iterator that points one past the last
* element in the %unordered_multimap.
*/
const_iterator
end() const noexcept
{ return _M_h.end(); }
const_iterator
cend() const noexcept
{ return _M_h.end(); }
//@}
// modifiers.
/**
* @brief Attempts to build and insert a std::pair into the
* %unordered_multimap.
*
* @param __args Arguments used to generate a new pair instance (see
* std::piecewise_contruct for passing arguments to each
* part of the pair constructor).
*
* @return An iterator that points to the inserted pair.
*
* This function attempts to build and insert a (key, value) %pair into
* the %unordered_multimap.
*
* Insertion requires amortized constant time.
*/
template<typename... _Args>
iterator
emplace(_Args&&... __args)
{ return _M_h.emplace(std::forward<_Args>(__args)...); }
/**
* @brief Attempts to build and insert a std::pair into the %unordered_multimap.
*
* @param __pos An iterator that serves as a hint as to where the pair
* should be inserted.
* @param __args Arguments used to generate a new pair instance (see
* std::piecewise_contruct for passing arguments to each
* part of the pair constructor).
* @return An iterator that points to the element with key of the
* std::pair built from @a __args.
*
* Note that the first parameter is only a hint and can potentially
* improve the performance of the insertion process. A bad hint would
* cause no gains in efficiency.
*
* See
* http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
* for more on @a hinting.
*
* Insertion requires amortized constant time.
*/
template<typename... _Args>
iterator
emplace_hint(const_iterator __pos, _Args&&... __args)
{ return _M_h.emplace_hint(__pos, std::forward<_Args>(__args)...); }
//@{
/**
* @brief Inserts a std::pair into the %unordered_multimap.
* @param __x Pair to be inserted (see std::make_pair for easy
* creation of pairs).
*
* @return An iterator that points to the inserted pair.
*
* Insertion requires amortized constant time.
*/
iterator
insert(const value_type& __x)
{ return _M_h.insert(__x); }
template<typename _Pair, typename = typename
std::enable_if<std::is_constructible<value_type,
_Pair&&>::value>::type>
iterator
insert(_Pair&& __x)
{ return _M_h.insert(std::move(__x)); }
//@}
//@{
/**
* @brief Inserts a std::pair into the %unordered_multimap.
* @param __hint An iterator that serves as a hint as to where the
* pair should be inserted.
* @param __x Pair to be inserted (see std::make_pair for easy creation
* of pairs).
* @return An iterator that points to the element with key of
* @a __x (may or may not be the %pair passed in).
*
* Note that the first parameter is only a hint and can potentially
* improve the performance of the insertion process. A bad hint would
* cause no gains in efficiency.
*
* See
* http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt07ch17.html
* for more on @a hinting.
*
* Insertion requires amortized constant time.
*/
iterator
insert(const_iterator __hint, const value_type& __x)
{ return _M_h.insert(__hint, __x); }
template<typename _Pair, typename = typename
std::enable_if<std::is_constructible<value_type,
_Pair&&>::value>::type>
iterator
insert(const_iterator __hint, _Pair&& __x)
{ return _M_h.insert(__hint, std::move(__x)); }
//@}
/**
* @brief A template function that attempts to insert a range of
* elements.
* @param __first Iterator pointing to the start of the range to be
* inserted.
* @param __last Iterator pointing to the end of the range.
*
* Complexity similar to that of the range constructor.
*/
template<typename _InputIterator>
void
insert(_InputIterator __first, _InputIterator __last)
{ _M_h.insert(__first, __last); }
/**
* @brief Attempts to insert a list of elements into the
* %unordered_multimap.
* @param __l A std::initializer_list<value_type> of elements
* to be inserted.
*
* Complexity similar to that of the range constructor.
*/
void
insert(initializer_list<value_type> __l)
{ _M_h.insert(__l); }
//@{
/**
* @brief Erases an element from an %unordered_multimap.
* @param __position An iterator pointing to the element to be erased.
* @return An iterator pointing to the element immediately following
* @a __position prior to the element being erased. If no such
* element exists, end() is returned.
*
* This function erases an element, pointed to by the given iterator,
* from an %unordered_multimap.
* Note that this function only erases the element, and that if the
* element is itself a pointer, the pointed-to memory is not touched in
* any way. Managing the pointer is the user's responsibility.
*/
iterator
erase(const_iterator __position)
{ return _M_h.erase(__position); }
// LWG 2059.
iterator
erase(iterator __it)
{ return _M_h.erase(__it); }
//@}
/**
* @brief Erases elements according to the provided key.
* @param __x Key of elements to be erased.
* @return The number of elements erased.
*
* This function erases all the elements located by the given key from
* an %unordered_multimap.
* Note that this function only erases the element, and that if the
* element is itself a pointer, the pointed-to memory is not touched in
* any way. Managing the pointer is the user's responsibility.
*/
size_type
erase(const key_type& __x)
{ return _M_h.erase(__x); }
/**
* @brief Erases a [__first,__last) range of elements from an
* %unordered_multimap.
* @param __first Iterator pointing to the start of the range to be
* erased.
* @param __last Iterator pointing to the end of the range to
* be erased.
* @return The iterator @a __last.
*
* This function erases a sequence of elements from an
* %unordered_multimap.
* Note that this function only erases the elements, and that if
* the element is itself a pointer, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibility.
*/
iterator
erase(const_iterator __first, const_iterator __last)
{ return _M_h.erase(__first, __last); }
/**
* Erases all elements in an %unordered_multimap.
* Note that this function only erases the elements, and that if the
* elements themselves are pointers, the pointed-to memory is not touched
* in any way. Managing the pointer is the user's responsibility.
*/
void
clear() noexcept
{ _M_h.clear(); }
/**
* @brief Swaps data with another %unordered_multimap.
* @param __x An %unordered_multimap of the same element and allocator
* types.
*
* This exchanges the elements between two %unordered_multimap in
* constant time.
* Note that the global std::swap() function is specialized such that
* std::swap(m1,m2) will feed to this function.
*/
void
swap(unordered_multimap& __x)
{ _M_h.swap(__x._M_h); }
// observers.
/// Returns the hash functor object with which the %unordered_multimap
/// was constructed.
hasher
hash_function() const
{ return _M_h.hash_function(); }
/// Returns the key comparison object with which the %unordered_multimap
/// was constructed.
key_equal
key_eq() const
{ return _M_h.key_eq(); }
// lookup.
//@{
/**
* @brief Tries to locate an element in an %unordered_multimap.
* @param __x Key to be located.
* @return Iterator pointing to sought-after element, or end() if not
* found.
*
* This function takes a key and tries to locate the element with which
* the key matches. If successful the function returns an iterator
* pointing to the sought after element. If unsuccessful it returns the
* past-the-end ( @c end() ) iterator.
*/
iterator
find(const key_type& __x)
{ return _M_h.find(__x); }
const_iterator
find(const key_type& __x) const
{ return _M_h.find(__x); }
//@}
/**
* @brief Finds the number of elements.
* @param __x Key to count.
* @return Number of elements with specified key.
*/
size_type
count(const key_type& __x) const
{ return _M_h.count(__x); }
//@{
/**
* @brief Finds a subsequence matching given key.
* @param __x Key to be located.
* @return Pair of iterators that possibly points to the subsequence
* matching given key.
*/
std::pair<iterator, iterator>
equal_range(const key_type& __x)
{ return _M_h.equal_range(__x); }
std::pair<const_iterator, const_iterator>
equal_range(const key_type& __x) const
{ return _M_h.equal_range(__x); }
//@}
// bucket interface.
/// Returns the number of buckets of the %unordered_multimap.
size_type
bucket_count() const noexcept
{ return _M_h.bucket_count(); }
/// Returns the maximum number of buckets of the %unordered_multimap.
size_type
max_bucket_count() const noexcept
{ return _M_h.max_bucket_count(); }
/*
* @brief Returns the number of elements in a given bucket.
* @param __n A bucket index.
* @return The number of elements in the bucket.
*/
size_type
bucket_size(size_type __n) const
{ return _M_h.bucket_size(__n); }
/*
* @brief Returns the bucket index of a given element.
* @param __key A key instance.
* @return The key bucket index.
*/
size_type
bucket(const key_type& __key) const
{ return _M_h.bucket(__key); }
/**
* @brief Returns a read/write iterator pointing to the first bucket
* element.
* @param __n The bucket index.
* @return A read/write local iterator.
*/
local_iterator
begin(size_type __n)
{ return _M_h.begin(__n); }
//@{
/**
* @brief Returns a read-only (constant) iterator pointing to the first
* bucket element.
* @param __n The bucket index.
* @return A read-only local iterator.
*/
const_local_iterator
begin(size_type __n) const
{ return _M_h.begin(__n); }
const_local_iterator
cbegin(size_type __n) const
{ return _M_h.cbegin(__n); }
//@}
/**
* @brief Returns a read/write iterator pointing to one past the last
* bucket elements.
* @param __n The bucket index.
* @return A read/write local iterator.
*/
local_iterator
end(size_type __n)
{ return _M_h.end(__n); }
//@{
/**
* @brief Returns a read-only (constant) iterator pointing to one past
* the last bucket elements.
* @param __n The bucket index.
* @return A read-only local iterator.
*/
const_local_iterator
end(size_type __n) const
{ return _M_h.end(__n); }
const_local_iterator
cend(size_type __n) const
{ return _M_h.cend(__n); }
//@}
// hash policy.
/// Returns the average number of elements per bucket.
float
load_factor() const noexcept
{ return _M_h.load_factor(); }
/// Returns a positive number that the %unordered_multimap tries to keep
/// the load factor less than or equal to.
float
max_load_factor() const noexcept
{ return _M_h.max_load_factor(); }
/**
* @brief Change the %unordered_multimap maximum load factor.
* @param __z The new maximum load factor.
*/
void
max_load_factor(float __z)
{ _M_h.max_load_factor(__z); }
/**
* @brief May rehash the %unordered_multimap.
* @param __n The new number of buckets.
*
* Rehash will occur only if the new number of buckets respect the
* %unordered_multimap maximum load factor.
*/
void
rehash(size_type __n)
{ _M_h.rehash(__n); }
/**
* @brief Prepare the %unordered_multimap for a specified number of
* elements.
* @param __n Number of elements required.
*
* Same as rehash(ceil(n / max_load_factor())).
*/
void
reserve(size_type __n)
{ _M_h.reserve(__n); }
template<typename _Key1, typename _Tp1, typename _Hash1, typename _Pred1,
typename _Alloc1>
friend bool
operator==(const unordered_multimap<_Key1, _Tp1,
_Hash1, _Pred1, _Alloc1>&,
const unordered_multimap<_Key1, _Tp1,
_Hash1, _Pred1, _Alloc1>&);
};
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
inline void
swap(unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
{ __x.swap(__y); }
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
inline void
swap(unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
{ __x.swap(__y); }
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
inline bool
operator==(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
{ return __x._M_h._M_equal(__y._M_h); }
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
inline bool
operator!=(const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
const unordered_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
{ return !(__x == __y); }
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
inline bool
operator==(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
{ return __x._M_h._M_equal(__y._M_h); }
template<class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
inline bool
operator!=(const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
const unordered_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
{ return !(__x == __y); }
_GLIBCXX_END_NAMESPACE_CONTAINER
template<typename _Key, typename _Tp, typename _Hash, typename _Pred,
typename _Alloc>
struct
is_copy_constructible<_GLIBCXX_STD_C::unordered_map<_Key, _Tp, _Hash,
_Pred, _Alloc>>
: __has_copy_insertable_val<_GLIBCXX_STD_C::unordered_map<_Key, _Tp, _Hash,
_Pred, _Alloc>>
{ };
template<typename _Key, typename _Tp, typename _Hash, typename _Pred,
typename _Alloc>
struct
is_copy_constructible<_GLIBCXX_STD_C::unordered_multimap<_Key, _Tp, _Hash,
_Pred, _Alloc>>
: __has_copy_insertable_val<_GLIBCXX_STD_C::unordered_multimap<_Key, _Tp,
_Hash, _Pred,
_Alloc>>
{ };
} // namespace std
#endif /* _UNORDERED_MAP_H */
|