1 // Core algorithmic facilities -*- C++ -*- 2 3 // Copyright (C) 2001-2013 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 3, 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 // Under Section 7 of GPL version 3, you are granted additional 17 // permissions described in the GCC Runtime Library Exception, version 18 // 3.1, as published by the Free Software Foundation. 19 20 // You should have received a copy of the GNU General Public License and 21 // a copy of the GCC Runtime Library Exception along with this program; 22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 23 // <http://www.gnu.org/licenses/>. 24 25 /* 26 * 27 * Copyright (c) 1994 28 * Hewlett-Packard Company 29 * 30 * Permission to use, copy, modify, distribute and sell this software 31 * and its documentation for any purpose is hereby granted without fee, 32 * provided that the above copyright notice appear in all copies and 33 * that both that copyright notice and this permission notice appear 34 * in supporting documentation. Hewlett-Packard Company makes no 35 * representations about the suitability of this software for any 36 * purpose. It is provided "as is" without express or implied warranty. 37 * 38 * 39 * Copyright (c) 1996-1998 40 * Silicon Graphics Computer Systems, Inc. 41 * 42 * Permission to use, copy, modify, distribute and sell this software 43 * and its documentation for any purpose is hereby granted without fee, 44 * provided that the above copyright notice appear in all copies and 45 * that both that copyright notice and this permission notice appear 46 * in supporting documentation. Silicon Graphics makes no 47 * representations about the suitability of this software for any 48 * purpose. It is provided "as is" without express or implied warranty. 49 */ 50 51 /** @file bits/stl_algobase.h 52 * This is an internal header file, included by other library headers. 53 * Do not attempt to use it directly. @headername{algorithm} 54 */ 55 56 #ifndef _STL_ALGOBASE_H 57 #define _STL_ALGOBASE_H 1 58 59 #include <bits/c++config.h> 60 #include <bits/functexcept.h> 61 #include <bits/cpp_type_traits.h> 62 #include <ext/type_traits.h> 63 #include <ext/numeric_traits.h> 64 #include <bits/stl_pair.h> 65 #include <bits/stl_iterator_base_types.h> 66 #include <bits/stl_iterator_base_funcs.h> 67 #include <bits/stl_iterator.h> 68 #include <bits/concept_check.h> 69 #include <debug/debug.h> 70 #include <bits/move.h> // For std::swap and _GLIBCXX_MOVE 71 72 namespace std _GLIBCXX_VISIBILITY(default) 73 { 74 _GLIBCXX_BEGIN_NAMESPACE_VERSION 75 76 #if __cplusplus < 201103L 77 // See http://gcc.gnu.org/ml/libstdc++/2004-08/msg00167.html: in a 78 // nutshell, we are partially implementing the resolution of DR 187, 79 // when it's safe, i.e., the value_types are equal. 80 template<bool _BoolType> 81 struct __iter_swap 82 { 83 template<typename _ForwardIterator1, typename _ForwardIterator2> 84 static void 85 iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b) 86 { 87 typedef typename iterator_traits<_ForwardIterator1>::value_type 88 _ValueType1; 89 _ValueType1 __tmp = _GLIBCXX_MOVE(*__a); 90 *__a = _GLIBCXX_MOVE(*__b); 91 *__b = _GLIBCXX_MOVE(__tmp); 92 } 93 }; 94 95 template<> 96 struct __iter_swap<true> 97 { 98 template<typename _ForwardIterator1, typename _ForwardIterator2> 99 static void 100 iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b) 101 { 102 swap(*__a, *__b); 103 } 104 }; 105 #endif 106 107 /** 108 * @brief Swaps the contents of two iterators. 109 * @ingroup mutating_algorithms 110 * @param __a An iterator. 111 * @param __b Another iterator. 112 * @return Nothing. 113 * 114 * This function swaps the values pointed to by two iterators, not the 115 * iterators themselves. 116 */ 117 template<typename _ForwardIterator1, typename _ForwardIterator2> 118 inline void 119 iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b) 120 { 121 // concept requirements 122 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< 123 _ForwardIterator1>) 124 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< 125 _ForwardIterator2>) 126 127 #if __cplusplus < 201103L 128 typedef typename iterator_traits<_ForwardIterator1>::value_type 129 _ValueType1; 130 typedef typename iterator_traits<_ForwardIterator2>::value_type 131 _ValueType2; 132 133 __glibcxx_function_requires(_ConvertibleConcept<_ValueType1, 134 _ValueType2>) 135 __glibcxx_function_requires(_ConvertibleConcept<_ValueType2, 136 _ValueType1>) 137 138 typedef typename iterator_traits<_ForwardIterator1>::reference 139 _ReferenceType1; 140 typedef typename iterator_traits<_ForwardIterator2>::reference 141 _ReferenceType2; 142 std::__iter_swap<__are_same<_ValueType1, _ValueType2>::__value 143 && __are_same<_ValueType1&, _ReferenceType1>::__value 144 && __are_same<_ValueType2&, _ReferenceType2>::__value>:: 145 iter_swap(__a, __b); 146 #else 147 swap(*__a, *__b); 148 #endif 149 } 150 151 /** 152 * @brief Swap the elements of two sequences. 153 * @ingroup mutating_algorithms 154 * @param __first1 A forward iterator. 155 * @param __last1 A forward iterator. 156 * @param __first2 A forward iterator. 157 * @return An iterator equal to @p first2+(last1-first1). 158 * 159 * Swaps each element in the range @p [first1,last1) with the 160 * corresponding element in the range @p [first2,(last1-first1)). 161 * The ranges must not overlap. 162 */ 163 template<typename _ForwardIterator1, typename _ForwardIterator2> 164 _ForwardIterator2 165 swap_ranges(_ForwardIterator1 __first1, _ForwardIterator1 __last1, 166 _ForwardIterator2 __first2) 167 { 168 // concept requirements 169 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< 170 _ForwardIterator1>) 171 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< 172 _ForwardIterator2>) 173 __glibcxx_requires_valid_range(__first1, __last1); 174 175 for (; __first1 != __last1; ++__first1, ++__first2) 176 std::iter_swap(__first1, __first2); 177 return __first2; 178 } 179 180 /** 181 * @brief This does what you think it does. 182 * @ingroup sorting_algorithms 183 * @param __a A thing of arbitrary type. 184 * @param __b Another thing of arbitrary type. 185 * @return The lesser of the parameters. 186 * 187 * This is the simple classic generic implementation. It will work on 188 * temporary expressions, since they are only evaluated once, unlike a 189 * preprocessor macro. 190 */ 191 template<typename _Tp> 192 inline const _Tp& 193 min(const _Tp& __a, const _Tp& __b) 194 { 195 // concept requirements 196 __glibcxx_function_requires(_LessThanComparableConcept<_Tp>) 197 //return __b < __a ? __b : __a; 198 if (__b < __a) 199 return __b; 200 return __a; 201 } 202 203 /** 204 * @brief This does what you think it does. 205 * @ingroup sorting_algorithms 206 * @param __a A thing of arbitrary type. 207 * @param __b Another thing of arbitrary type. 208 * @return The greater of the parameters. 209 * 210 * This is the simple classic generic implementation. It will work on 211 * temporary expressions, since they are only evaluated once, unlike a 212 * preprocessor macro. 213 */ 214 template<typename _Tp> 215 inline const _Tp& 216 max(const _Tp& __a, const _Tp& __b) 217 { 218 // concept requirements 219 __glibcxx_function_requires(_LessThanComparableConcept<_Tp>) 220 //return __a < __b ? __b : __a; 221 if (__a < __b) 222 return __b; 223 return __a; 224 } 225 226 /** 227 * @brief This does what you think it does. 228 * @ingroup sorting_algorithms 229 * @param __a A thing of arbitrary type. 230 * @param __b Another thing of arbitrary type. 231 * @param __comp A @link comparison_functors comparison functor@endlink. 232 * @return The lesser of the parameters. 233 * 234 * This will work on temporary expressions, since they are only evaluated 235 * once, unlike a preprocessor macro. 236 */ 237 template<typename _Tp, typename _Compare> 238 inline const _Tp& 239 min(const _Tp& __a, const _Tp& __b, _Compare __comp) 240 { 241 //return __comp(__b, __a) ? __b : __a; 242 if (__comp(__b, __a)) 243 return __b; 244 return __a; 245 } 246 247 /** 248 * @brief This does what you think it does. 249 * @ingroup sorting_algorithms 250 * @param __a A thing of arbitrary type. 251 * @param __b Another thing of arbitrary type. 252 * @param __comp A @link comparison_functors comparison functor@endlink. 253 * @return The greater of the parameters. 254 * 255 * This will work on temporary expressions, since they are only evaluated 256 * once, unlike a preprocessor macro. 257 */ 258 template<typename _Tp, typename _Compare> 259 inline const _Tp& 260 max(const _Tp& __a, const _Tp& __b, _Compare __comp) 261 { 262 //return __comp(__a, __b) ? __b : __a; 263 if (__comp(__a, __b)) 264 return __b; 265 return __a; 266 } 267 268 // If _Iterator is a __normal_iterator return its base (a plain pointer, 269 // normally) otherwise return it untouched. See copy, fill, ... 270 template<typename _Iterator> 271 struct _Niter_base 272 : _Iter_base<_Iterator, __is_normal_iterator<_Iterator>::__value> 273 { }; 274 275 template<typename _Iterator> 276 inline typename _Niter_base<_Iterator>::iterator_type 277 __niter_base(_Iterator __it) 278 { return std::_Niter_base<_Iterator>::_S_base(__it); } 279 280 // Likewise, for move_iterator. 281 template<typename _Iterator> 282 struct _Miter_base 283 : _Iter_base<_Iterator, __is_move_iterator<_Iterator>::__value> 284 { }; 285 286 template<typename _Iterator> 287 inline typename _Miter_base<_Iterator>::iterator_type 288 __miter_base(_Iterator __it) 289 { return std::_Miter_base<_Iterator>::_S_base(__it); } 290 291 // All of these auxiliary structs serve two purposes. (1) Replace 292 // calls to copy with memmove whenever possible. (Memmove, not memcpy, 293 // because the input and output ranges are permitted to overlap.) 294 // (2) If we're using random access iterators, then write the loop as 295 // a for loop with an explicit count. 296 297 template<bool, bool, typename> 298 struct __copy_move 299 { 300 template<typename _II, typename _OI> 301 static _OI 302 __copy_m(_II __first, _II __last, _OI __result) 303 { 304 for (; __first != __last; ++__result, ++__first) 305 *__result = *__first; 306 return __result; 307 } 308 }; 309 310 #if __cplusplus >= 201103L 311 template<typename _Category> 312 struct __copy_move<true, false, _Category> 313 { 314 template<typename _II, typename _OI> 315 static _OI 316 __copy_m(_II __first, _II __last, _OI __result) 317 { 318 for (; __first != __last; ++__result, ++__first) 319 *__result = std::move(*__first); 320 return __result; 321 } 322 }; 323 #endif 324 325 template<> 326 struct __copy_move<false, false, random_access_iterator_tag> 327 { 328 template<typename _II, typename _OI> 329 static _OI 330 __copy_m(_II __first, _II __last, _OI __result) 331 { 332 typedef typename iterator_traits<_II>::difference_type _Distance; 333 for(_Distance __n = __last - __first; __n > 0; --__n) 334 { 335 *__result = *__first; 336 ++__first; 337 ++__result; 338 } 339 return __result; 340 } 341 }; 342 343 #if __cplusplus >= 201103L 344 template<> 345 struct __copy_move<true, false, random_access_iterator_tag> 346 { 347 template<typename _II, typename _OI> 348 static _OI 349 __copy_m(_II __first, _II __last, _OI __result) 350 { 351 typedef typename iterator_traits<_II>::difference_type _Distance; 352 for(_Distance __n = __last - __first; __n > 0; --__n) 353 { 354 *__result = std::move(*__first); 355 ++__first; 356 ++__result; 357 } 358 return __result; 359 } 360 }; 361 #endif 362 363 template<bool _IsMove> 364 struct __copy_move<_IsMove, true, random_access_iterator_tag> 365 { 366 template<typename _Tp> 367 static _Tp* 368 __copy_m(const _Tp* __first, const _Tp* __last, _Tp* __result) 369 { 370 const ptrdiff_t _Num = __last - __first; 371 if (_Num) 372 __builtin_memmove(__result, __first, sizeof(_Tp) * _Num); 373 return __result + _Num; 374 } 375 }; 376 377 template<bool _IsMove, typename _II, typename _OI> 378 inline _OI 379 __copy_move_a(_II __first, _II __last, _OI __result) 380 { 381 typedef typename iterator_traits<_II>::value_type _ValueTypeI; 382 typedef typename iterator_traits<_OI>::value_type _ValueTypeO; 383 typedef typename iterator_traits<_II>::iterator_category _Category; 384 const bool __simple = (__is_trivial(_ValueTypeI) 385 && __is_pointer<_II>::__value 386 && __is_pointer<_OI>::__value 387 && __are_same<_ValueTypeI, _ValueTypeO>::__value); 388 389 return std::__copy_move<_IsMove, __simple, 390 _Category>::__copy_m(__first, __last, __result); 391 } 392 393 // Helpers for streambuf iterators (either istream or ostream). 394 // NB: avoid including <iosfwd>, relatively large. 395 template<typename _CharT> 396 struct char_traits; 397 398 template<typename _CharT, typename _Traits> 399 class istreambuf_iterator; 400 401 template<typename _CharT, typename _Traits> 402 class ostreambuf_iterator; 403 404 template<bool _IsMove, typename _CharT> 405 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 406 ostreambuf_iterator<_CharT, char_traits<_CharT> > >::__type 407 __copy_move_a2(_CharT*, _CharT*, 408 ostreambuf_iterator<_CharT, char_traits<_CharT> >); 409 410 template<bool _IsMove, typename _CharT> 411 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 412 ostreambuf_iterator<_CharT, char_traits<_CharT> > >::__type 413 __copy_move_a2(const _CharT*, const _CharT*, 414 ostreambuf_iterator<_CharT, char_traits<_CharT> >); 415 416 template<bool _IsMove, typename _CharT> 417 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 418 _CharT*>::__type 419 __copy_move_a2(istreambuf_iterator<_CharT, char_traits<_CharT> >, 420 istreambuf_iterator<_CharT, char_traits<_CharT> >, _CharT*); 421 422 template<bool _IsMove, typename _II, typename _OI> 423 inline _OI 424 __copy_move_a2(_II __first, _II __last, _OI __result) 425 { 426 return _OI(std::__copy_move_a<_IsMove>(std::__niter_base(__first), 427 std::__niter_base(__last), 428 std::__niter_base(__result))); 429 } 430 431 /** 432 * @brief Copies the range [first,last) into result. 433 * @ingroup mutating_algorithms 434 * @param __first An input iterator. 435 * @param __last An input iterator. 436 * @param __result An output iterator. 437 * @return result + (first - last) 438 * 439 * This inline function will boil down to a call to @c memmove whenever 440 * possible. Failing that, if random access iterators are passed, then the 441 * loop count will be known (and therefore a candidate for compiler 442 * optimizations such as unrolling). Result may not be contained within 443 * [first,last); the copy_backward function should be used instead. 444 * 445 * Note that the end of the output range is permitted to be contained 446 * within [first,last). 447 */ 448 template<typename _II, typename _OI> 449 inline _OI 450 copy(_II __first, _II __last, _OI __result) 451 { 452 // concept requirements 453 __glibcxx_function_requires(_InputIteratorConcept<_II>) 454 __glibcxx_function_requires(_OutputIteratorConcept<_OI, 455 typename iterator_traits<_II>::value_type>) 456 __glibcxx_requires_valid_range(__first, __last); 457 458 return (std::__copy_move_a2<__is_move_iterator<_II>::__value> 459 (std::__miter_base(__first), std::__miter_base(__last), 460 __result)); 461 } 462 463 #if __cplusplus >= 201103L 464 /** 465 * @brief Moves the range [first,last) into result. 466 * @ingroup mutating_algorithms 467 * @param __first An input iterator. 468 * @param __last An input iterator. 469 * @param __result An output iterator. 470 * @return result + (first - last) 471 * 472 * This inline function will boil down to a call to @c memmove whenever 473 * possible. Failing that, if random access iterators are passed, then the 474 * loop count will be known (and therefore a candidate for compiler 475 * optimizations such as unrolling). Result may not be contained within 476 * [first,last); the move_backward function should be used instead. 477 * 478 * Note that the end of the output range is permitted to be contained 479 * within [first,last). 480 */ 481 template<typename _II, typename _OI> 482 inline _OI 483 move(_II __first, _II __last, _OI __result) 484 { 485 // concept requirements 486 __glibcxx_function_requires(_InputIteratorConcept<_II>) 487 __glibcxx_function_requires(_OutputIteratorConcept<_OI, 488 typename iterator_traits<_II>::value_type>) 489 __glibcxx_requires_valid_range(__first, __last); 490 491 return std::__copy_move_a2<true>(std::__miter_base(__first), 492 std::__miter_base(__last), __result); 493 } 494 495 #define _GLIBCXX_MOVE3(_Tp, _Up, _Vp) std::move(_Tp, _Up, _Vp) 496 #else 497 #define _GLIBCXX_MOVE3(_Tp, _Up, _Vp) std::copy(_Tp, _Up, _Vp) 498 #endif 499 500 template<bool, bool, typename> 501 struct __copy_move_backward 502 { 503 template<typename _BI1, typename _BI2> 504 static _BI2 505 __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result) 506 { 507 while (__first != __last) 508 *--__result = *--__last; 509 return __result; 510 } 511 }; 512 513 #if __cplusplus >= 201103L 514 template<typename _Category> 515 struct __copy_move_backward<true, false, _Category> 516 { 517 template<typename _BI1, typename _BI2> 518 static _BI2 519 __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result) 520 { 521 while (__first != __last) 522 *--__result = std::move(*--__last); 523 return __result; 524 } 525 }; 526 #endif 527 528 template<> 529 struct __copy_move_backward<false, false, random_access_iterator_tag> 530 { 531 template<typename _BI1, typename _BI2> 532 static _BI2 533 __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result) 534 { 535 typename iterator_traits<_BI1>::difference_type __n; 536 for (__n = __last - __first; __n > 0; --__n) 537 *--__result = *--__last; 538 return __result; 539 } 540 }; 541 542 #if __cplusplus >= 201103L 543 template<> 544 struct __copy_move_backward<true, false, random_access_iterator_tag> 545 { 546 template<typename _BI1, typename _BI2> 547 static _BI2 548 __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result) 549 { 550 typename iterator_traits<_BI1>::difference_type __n; 551 for (__n = __last - __first; __n > 0; --__n) 552 *--__result = std::move(*--__last); 553 return __result; 554 } 555 }; 556 #endif 557 558 template<bool _IsMove> 559 struct __copy_move_backward<_IsMove, true, random_access_iterator_tag> 560 { 561 template<typename _Tp> 562 static _Tp* 563 __copy_move_b(const _Tp* __first, const _Tp* __last, _Tp* __result) 564 { 565 const ptrdiff_t _Num = __last - __first; 566 if (_Num) 567 __builtin_memmove(__result - _Num, __first, sizeof(_Tp) * _Num); 568 return __result - _Num; 569 } 570 }; 571 572 template<bool _IsMove, typename _BI1, typename _BI2> 573 inline _BI2 574 __copy_move_backward_a(_BI1 __first, _BI1 __last, _BI2 __result) 575 { 576 typedef typename iterator_traits<_BI1>::value_type _ValueType1; 577 typedef typename iterator_traits<_BI2>::value_type _ValueType2; 578 typedef typename iterator_traits<_BI1>::iterator_category _Category; 579 const bool __simple = (__is_trivial(_ValueType1) 580 && __is_pointer<_BI1>::__value 581 && __is_pointer<_BI2>::__value 582 && __are_same<_ValueType1, _ValueType2>::__value); 583 584 return std::__copy_move_backward<_IsMove, __simple, 585 _Category>::__copy_move_b(__first, 586 __last, 587 __result); 588 } 589 590 template<bool _IsMove, typename _BI1, typename _BI2> 591 inline _BI2 592 __copy_move_backward_a2(_BI1 __first, _BI1 __last, _BI2 __result) 593 { 594 return _BI2(std::__copy_move_backward_a<_IsMove> 595 (std::__niter_base(__first), std::__niter_base(__last), 596 std::__niter_base(__result))); 597 } 598 599 /** 600 * @brief Copies the range [first,last) into result. 601 * @ingroup mutating_algorithms 602 * @param __first A bidirectional iterator. 603 * @param __last A bidirectional iterator. 604 * @param __result A bidirectional iterator. 605 * @return result - (first - last) 606 * 607 * The function has the same effect as copy, but starts at the end of the 608 * range and works its way to the start, returning the start of the result. 609 * This inline function will boil down to a call to @c memmove whenever 610 * possible. Failing that, if random access iterators are passed, then the 611 * loop count will be known (and therefore a candidate for compiler 612 * optimizations such as unrolling). 613 * 614 * Result may not be in the range (first,last]. Use copy instead. Note 615 * that the start of the output range may overlap [first,last). 616 */ 617 template<typename _BI1, typename _BI2> 618 inline _BI2 619 copy_backward(_BI1 __first, _BI1 __last, _BI2 __result) 620 { 621 // concept requirements 622 __glibcxx_function_requires(_BidirectionalIteratorConcept<_BI1>) 623 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<_BI2>) 624 __glibcxx_function_requires(_ConvertibleConcept< 625 typename iterator_traits<_BI1>::value_type, 626 typename iterator_traits<_BI2>::value_type>) 627 __glibcxx_requires_valid_range(__first, __last); 628 629 return (std::__copy_move_backward_a2<__is_move_iterator<_BI1>::__value> 630 (std::__miter_base(__first), std::__miter_base(__last), 631 __result)); 632 } 633 634 #if __cplusplus >= 201103L 635 /** 636 * @brief Moves the range [first,last) into result. 637 * @ingroup mutating_algorithms 638 * @param __first A bidirectional iterator. 639 * @param __last A bidirectional iterator. 640 * @param __result A bidirectional iterator. 641 * @return result - (first - last) 642 * 643 * The function has the same effect as move, but starts at the end of the 644 * range and works its way to the start, returning the start of the result. 645 * This inline function will boil down to a call to @c memmove whenever 646 * possible. Failing that, if random access iterators are passed, then the 647 * loop count will be known (and therefore a candidate for compiler 648 * optimizations such as unrolling). 649 * 650 * Result may not be in the range (first,last]. Use move instead. Note 651 * that the start of the output range may overlap [first,last). 652 */ 653 template<typename _BI1, typename _BI2> 654 inline _BI2 655 move_backward(_BI1 __first, _BI1 __last, _BI2 __result) 656 { 657 // concept requirements 658 __glibcxx_function_requires(_BidirectionalIteratorConcept<_BI1>) 659 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<_BI2>) 660 __glibcxx_function_requires(_ConvertibleConcept< 661 typename iterator_traits<_BI1>::value_type, 662 typename iterator_traits<_BI2>::value_type>) 663 __glibcxx_requires_valid_range(__first, __last); 664 665 return std::__copy_move_backward_a2<true>(std::__miter_base(__first), 666 std::__miter_base(__last), 667 __result); 668 } 669 670 #define _GLIBCXX_MOVE_BACKWARD3(_Tp, _Up, _Vp) std::move_backward(_Tp, _Up, _Vp) 671 #else 672 #define _GLIBCXX_MOVE_BACKWARD3(_Tp, _Up, _Vp) std::copy_backward(_Tp, _Up, _Vp) 673 #endif 674 675 template<typename _ForwardIterator, typename _Tp> 676 inline typename 677 __gnu_cxx::__enable_if<!__is_scalar<_Tp>::__value, void>::__type 678 __fill_a(_ForwardIterator __first, _ForwardIterator __last, 679 const _Tp& __value) 680 { 681 for (; __first != __last; ++__first) 682 *__first = __value; 683 } 684 685 template<typename _ForwardIterator, typename _Tp> 686 inline typename 687 __gnu_cxx::__enable_if<__is_scalar<_Tp>::__value, void>::__type 688 __fill_a(_ForwardIterator __first, _ForwardIterator __last, 689 const _Tp& __value) 690 { 691 const _Tp __tmp = __value; 692 for (; __first != __last; ++__first) 693 *__first = __tmp; 694 } 695 696 // Specialization: for char types we can use memset. 697 template<typename _Tp> 698 inline typename 699 __gnu_cxx::__enable_if<__is_byte<_Tp>::__value, void>::__type 700 __fill_a(_Tp* __first, _Tp* __last, const _Tp& __c) 701 { 702 const _Tp __tmp = __c; 703 __builtin_memset(__first, static_cast<unsigned char>(__tmp), 704 __last - __first); 705 } 706 707 /** 708 * @brief Fills the range [first,last) with copies of value. 709 * @ingroup mutating_algorithms 710 * @param __first A forward iterator. 711 * @param __last A forward iterator. 712 * @param __value A reference-to-const of arbitrary type. 713 * @return Nothing. 714 * 715 * This function fills a range with copies of the same value. For char 716 * types filling contiguous areas of memory, this becomes an inline call 717 * to @c memset or @c wmemset. 718 */ 719 template<typename _ForwardIterator, typename _Tp> 720 inline void 721 fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) 722 { 723 // concept requirements 724 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< 725 _ForwardIterator>) 726 __glibcxx_requires_valid_range(__first, __last); 727 728 std::__fill_a(std::__niter_base(__first), std::__niter_base(__last), 729 __value); 730 } 731 732 template<typename _OutputIterator, typename _Size, typename _Tp> 733 inline typename 734 __gnu_cxx::__enable_if<!__is_scalar<_Tp>::__value, _OutputIterator>::__type 735 __fill_n_a(_OutputIterator __first, _Size __n, const _Tp& __value) 736 { 737 for (__decltype(__n + 0) __niter = __n; 738 __niter > 0; --__niter, ++__first) 739 *__first = __value; 740 return __first; 741 } 742 743 template<typename _OutputIterator, typename _Size, typename _Tp> 744 inline typename 745 __gnu_cxx::__enable_if<__is_scalar<_Tp>::__value, _OutputIterator>::__type 746 __fill_n_a(_OutputIterator __first, _Size __n, const _Tp& __value) 747 { 748 const _Tp __tmp = __value; 749 for (__decltype(__n + 0) __niter = __n; 750 __niter > 0; --__niter, ++__first) 751 *__first = __tmp; 752 return __first; 753 } 754 755 template<typename _Size, typename _Tp> 756 inline typename 757 __gnu_cxx::__enable_if<__is_byte<_Tp>::__value, _Tp*>::__type 758 __fill_n_a(_Tp* __first, _Size __n, const _Tp& __c) 759 { 760 std::__fill_a(__first, __first + __n, __c); 761 return __first + __n; 762 } 763 764 /** 765 * @brief Fills the range [first,first+n) with copies of value. 766 * @ingroup mutating_algorithms 767 * @param __first An output iterator. 768 * @param __n The count of copies to perform. 769 * @param __value A reference-to-const of arbitrary type. 770 * @return The iterator at first+n. 771 * 772 * This function fills a range with copies of the same value. For char 773 * types filling contiguous areas of memory, this becomes an inline call 774 * to @c memset or @ wmemset. 775 * 776 * _GLIBCXX_RESOLVE_LIB_DEFECTS 777 * DR 865. More algorithms that throw away information 778 */ 779 template<typename _OI, typename _Size, typename _Tp> 780 inline _OI 781 fill_n(_OI __first, _Size __n, const _Tp& __value) 782 { 783 // concept requirements 784 __glibcxx_function_requires(_OutputIteratorConcept<_OI, _Tp>) 785 786 return _OI(std::__fill_n_a(std::__niter_base(__first), __n, __value)); 787 } 788 789 template<bool _BoolType> 790 struct __equal 791 { 792 template<typename _II1, typename _II2> 793 static bool 794 equal(_II1 __first1, _II1 __last1, _II2 __first2) 795 { 796 for (; __first1 != __last1; ++__first1, ++__first2) 797 if (!(*__first1 == *__first2)) 798 return false; 799 return true; 800 } 801 }; 802 803 template<> 804 struct __equal<true> 805 { 806 template<typename _Tp> 807 static bool 808 equal(const _Tp* __first1, const _Tp* __last1, const _Tp* __first2) 809 { 810 return !__builtin_memcmp(__first1, __first2, sizeof(_Tp) 811 * (__last1 - __first1)); 812 } 813 }; 814 815 template<typename _II1, typename _II2> 816 inline bool 817 __equal_aux(_II1 __first1, _II1 __last1, _II2 __first2) 818 { 819 typedef typename iterator_traits<_II1>::value_type _ValueType1; 820 typedef typename iterator_traits<_II2>::value_type _ValueType2; 821 const bool __simple = ((__is_integer<_ValueType1>::__value 822 || __is_pointer<_ValueType1>::__value) 823 && __is_pointer<_II1>::__value 824 && __is_pointer<_II2>::__value 825 && __are_same<_ValueType1, _ValueType2>::__value); 826 827 return std::__equal<__simple>::equal(__first1, __last1, __first2); 828 } 829 830 831 template<typename, typename> 832 struct __lc_rai 833 { 834 template<typename _II1, typename _II2> 835 static _II1 836 __newlast1(_II1, _II1 __last1, _II2, _II2) 837 { return __last1; } 838 839 template<typename _II> 840 static bool 841 __cnd2(_II __first, _II __last) 842 { return __first != __last; } 843 }; 844 845 template<> 846 struct __lc_rai<random_access_iterator_tag, random_access_iterator_tag> 847 { 848 template<typename _RAI1, typename _RAI2> 849 static _RAI1 850 __newlast1(_RAI1 __first1, _RAI1 __last1, 851 _RAI2 __first2, _RAI2 __last2) 852 { 853 const typename iterator_traits<_RAI1>::difference_type 854 __diff1 = __last1 - __first1; 855 const typename iterator_traits<_RAI2>::difference_type 856 __diff2 = __last2 - __first2; 857 return __diff2 < __diff1 ? __first1 + __diff2 : __last1; 858 } 859 860 template<typename _RAI> 861 static bool 862 __cnd2(_RAI, _RAI) 863 { return true; } 864 }; 865 866 template<bool _BoolType> 867 struct __lexicographical_compare 868 { 869 template<typename _II1, typename _II2> 870 static bool __lc(_II1, _II1, _II2, _II2); 871 }; 872 873 template<bool _BoolType> 874 template<typename _II1, typename _II2> 875 bool 876 __lexicographical_compare<_BoolType>:: 877 __lc(_II1 __first1, _II1 __last1, _II2 __first2, _II2 __last2) 878 { 879 typedef typename iterator_traits<_II1>::iterator_category _Category1; 880 typedef typename iterator_traits<_II2>::iterator_category _Category2; 881 typedef std::__lc_rai<_Category1, _Category2> __rai_type; 882 883 __last1 = __rai_type::__newlast1(__first1, __last1, 884 __first2, __last2); 885 for (; __first1 != __last1 && __rai_type::__cnd2(__first2, __last2); 886 ++__first1, ++__first2) 887 { 888 if (*__first1 < *__first2) 889 return true; 890 if (*__first2 < *__first1) 891 return false; 892 } 893 return __first1 == __last1 && __first2 != __last2; 894 } 895 896 template<> 897 struct __lexicographical_compare<true> 898 { 899 template<typename _Tp, typename _Up> 900 static bool 901 __lc(const _Tp* __first1, const _Tp* __last1, 902 const _Up* __first2, const _Up* __last2) 903 { 904 const size_t __len1 = __last1 - __first1; 905 const size_t __len2 = __last2 - __first2; 906 const int __result = __builtin_memcmp(__first1, __first2, 907 std::min(__len1, __len2)); 908 return __result != 0 ? __result < 0 : __len1 < __len2; 909 } 910 }; 911 912 template<typename _II1, typename _II2> 913 inline bool 914 __lexicographical_compare_aux(_II1 __first1, _II1 __last1, 915 _II2 __first2, _II2 __last2) 916 { 917 typedef typename iterator_traits<_II1>::value_type _ValueType1; 918 typedef typename iterator_traits<_II2>::value_type _ValueType2; 919 const bool __simple = 920 (__is_byte<_ValueType1>::__value && __is_byte<_ValueType2>::__value 921 && !__gnu_cxx::__numeric_traits<_ValueType1>::__is_signed 922 && !__gnu_cxx::__numeric_traits<_ValueType2>::__is_signed 923 && __is_pointer<_II1>::__value 924 && __is_pointer<_II2>::__value); 925 926 return std::__lexicographical_compare<__simple>::__lc(__first1, __last1, 927 __first2, __last2); 928 } 929 930 /** 931 * @brief Finds the first position in which @a val could be inserted 932 * without changing the ordering. 933 * @param __first An iterator. 934 * @param __last Another iterator. 935 * @param __val The search term. 936 * @return An iterator pointing to the first element <em>not less 937 * than</em> @a val, or end() if every element is less than 938 * @a val. 939 * @ingroup binary_search_algorithms 940 */ 941 template<typename _ForwardIterator, typename _Tp> 942 _ForwardIterator 943 lower_bound(_ForwardIterator __first, _ForwardIterator __last, 944 const _Tp& __val) 945 { 946 #ifdef _GLIBCXX_CONCEPT_CHECKS 947 typedef typename iterator_traits<_ForwardIterator>::value_type 948 _ValueType; 949 #endif 950 typedef typename iterator_traits<_ForwardIterator>::difference_type 951 _DistanceType; 952 953 // concept requirements 954 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) 955 __glibcxx_function_requires(_LessThanOpConcept<_ValueType, _Tp>) 956 __glibcxx_requires_partitioned_lower(__first, __last, __val); 957 958 _DistanceType __len = std::distance(__first, __last); 959 960 while (__len > 0) 961 { 962 _DistanceType __half = __len >> 1; 963 _ForwardIterator __middle = __first; 964 std::advance(__middle, __half); 965 if (*__middle < __val) 966 { 967 __first = __middle; 968 ++__first; 969 __len = __len - __half - 1; 970 } 971 else 972 __len = __half; 973 } 974 return __first; 975 } 976 977 /// This is a helper function for the sort routines and for random.tcc. 978 // Precondition: __n > 0. 979 inline _GLIBCXX_CONSTEXPR int 980 __lg(int __n) 981 { return sizeof(int) * __CHAR_BIT__ - 1 - __builtin_clz(__n); } 982 983 inline _GLIBCXX_CONSTEXPR unsigned 984 __lg(unsigned __n) 985 { return sizeof(int) * __CHAR_BIT__ - 1 - __builtin_clz(__n); } 986 987 inline _GLIBCXX_CONSTEXPR long 988 __lg(long __n) 989 { return sizeof(long) * __CHAR_BIT__ - 1 - __builtin_clzl(__n); } 990 991 inline _GLIBCXX_CONSTEXPR unsigned long 992 __lg(unsigned long __n) 993 { return sizeof(long) * __CHAR_BIT__ - 1 - __builtin_clzl(__n); } 994 995 inline _GLIBCXX_CONSTEXPR long long 996 __lg(long long __n) 997 { return sizeof(long long) * __CHAR_BIT__ - 1 - __builtin_clzll(__n); } 998 999 inline _GLIBCXX_CONSTEXPR unsigned long long 1000 __lg(unsigned long long __n) 1001 { return sizeof(long long) * __CHAR_BIT__ - 1 - __builtin_clzll(__n); } 1002 1003 _GLIBCXX_END_NAMESPACE_VERSION 1004 1005 _GLIBCXX_BEGIN_NAMESPACE_ALGO 1006 1007 /** 1008 * @brief Tests a range for element-wise equality. 1009 * @ingroup non_mutating_algorithms 1010 * @param __first1 An input iterator. 1011 * @param __last1 An input iterator. 1012 * @param __first2 An input iterator. 1013 * @return A boolean true or false. 1014 * 1015 * This compares the elements of two ranges using @c == and returns true or 1016 * false depending on whether all of the corresponding elements of the 1017 * ranges are equal. 1018 */ 1019 template<typename _II1, typename _II2> 1020 inline bool 1021 equal(_II1 __first1, _II1 __last1, _II2 __first2) 1022 { 1023 // concept requirements 1024 __glibcxx_function_requires(_InputIteratorConcept<_II1>) 1025 __glibcxx_function_requires(_InputIteratorConcept<_II2>) 1026 __glibcxx_function_requires(_EqualOpConcept< 1027 typename iterator_traits<_II1>::value_type, 1028 typename iterator_traits<_II2>::value_type>) 1029 __glibcxx_requires_valid_range(__first1, __last1); 1030 1031 return std::__equal_aux(std::__niter_base(__first1), 1032 std::__niter_base(__last1), 1033 std::__niter_base(__first2)); 1034 } 1035 1036 /** 1037 * @brief Tests a range for element-wise equality. 1038 * @ingroup non_mutating_algorithms 1039 * @param __first1 An input iterator. 1040 * @param __last1 An input iterator. 1041 * @param __first2 An input iterator. 1042 * @param __binary_pred A binary predicate @link functors 1043 * functor@endlink. 1044 * @return A boolean true or false. 1045 * 1046 * This compares the elements of two ranges using the binary_pred 1047 * parameter, and returns true or 1048 * false depending on whether all of the corresponding elements of the 1049 * ranges are equal. 1050 */ 1051 template<typename _IIter1, typename _IIter2, typename _BinaryPredicate> 1052 inline bool 1053 equal(_IIter1 __first1, _IIter1 __last1, 1054 _IIter2 __first2, _BinaryPredicate __binary_pred) 1055 { 1056 // concept requirements 1057 __glibcxx_function_requires(_InputIteratorConcept<_IIter1>) 1058 __glibcxx_function_requires(_InputIteratorConcept<_IIter2>) 1059 __glibcxx_requires_valid_range(__first1, __last1); 1060 1061 for (; __first1 != __last1; ++__first1, ++__first2) 1062 if (!bool(__binary_pred(*__first1, *__first2))) 1063 return false; 1064 return true; 1065 } 1066 1067 /** 1068 * @brief Performs @b dictionary comparison on ranges. 1069 * @ingroup sorting_algorithms 1070 * @param __first1 An input iterator. 1071 * @param __last1 An input iterator. 1072 * @param __first2 An input iterator. 1073 * @param __last2 An input iterator. 1074 * @return A boolean true or false. 1075 * 1076 * <em>Returns true if the sequence of elements defined by the range 1077 * [first1,last1) is lexicographically less than the sequence of elements 1078 * defined by the range [first2,last2). Returns false otherwise.</em> 1079 * (Quoted from [25.3.8]/1.) If the iterators are all character pointers, 1080 * then this is an inline call to @c memcmp. 1081 */ 1082 template<typename _II1, typename _II2> 1083 inline bool 1084 lexicographical_compare(_II1 __first1, _II1 __last1, 1085 _II2 __first2, _II2 __last2) 1086 { 1087 #ifdef _GLIBCXX_CONCEPT_CHECKS 1088 // concept requirements 1089 typedef typename iterator_traits<_II1>::value_type _ValueType1; 1090 typedef typename iterator_traits<_II2>::value_type _ValueType2; 1091 #endif 1092 __glibcxx_function_requires(_InputIteratorConcept<_II1>) 1093 __glibcxx_function_requires(_InputIteratorConcept<_II2>) 1094 __glibcxx_function_requires(_LessThanOpConcept<_ValueType1, _ValueType2>) 1095 __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>) 1096 __glibcxx_requires_valid_range(__first1, __last1); 1097 __glibcxx_requires_valid_range(__first2, __last2); 1098 1099 return std::__lexicographical_compare_aux(std::__niter_base(__first1), 1100 std::__niter_base(__last1), 1101 std::__niter_base(__first2), 1102 std::__niter_base(__last2)); 1103 } 1104 1105 /** 1106 * @brief Performs @b dictionary comparison on ranges. 1107 * @ingroup sorting_algorithms 1108 * @param __first1 An input iterator. 1109 * @param __last1 An input iterator. 1110 * @param __first2 An input iterator. 1111 * @param __last2 An input iterator. 1112 * @param __comp A @link comparison_functors comparison functor@endlink. 1113 * @return A boolean true or false. 1114 * 1115 * The same as the four-parameter @c lexicographical_compare, but uses the 1116 * comp parameter instead of @c <. 1117 */ 1118 template<typename _II1, typename _II2, typename _Compare> 1119 bool 1120 lexicographical_compare(_II1 __first1, _II1 __last1, 1121 _II2 __first2, _II2 __last2, _Compare __comp) 1122 { 1123 typedef typename iterator_traits<_II1>::iterator_category _Category1; 1124 typedef typename iterator_traits<_II2>::iterator_category _Category2; 1125 typedef std::__lc_rai<_Category1, _Category2> __rai_type; 1126 1127 // concept requirements 1128 __glibcxx_function_requires(_InputIteratorConcept<_II1>) 1129 __glibcxx_function_requires(_InputIteratorConcept<_II2>) 1130 __glibcxx_requires_valid_range(__first1, __last1); 1131 __glibcxx_requires_valid_range(__first2, __last2); 1132 1133 __last1 = __rai_type::__newlast1(__first1, __last1, __first2, __last2); 1134 for (; __first1 != __last1 && __rai_type::__cnd2(__first2, __last2); 1135 ++__first1, ++__first2) 1136 { 1137 if (__comp(*__first1, *__first2)) 1138 return true; 1139 if (__comp(*__first2, *__first1)) 1140 return false; 1141 } 1142 return __first1 == __last1 && __first2 != __last2; 1143 } 1144 1145 /** 1146 * @brief Finds the places in ranges which don't match. 1147 * @ingroup non_mutating_algorithms 1148 * @param __first1 An input iterator. 1149 * @param __last1 An input iterator. 1150 * @param __first2 An input iterator. 1151 * @return A pair of iterators pointing to the first mismatch. 1152 * 1153 * This compares the elements of two ranges using @c == and returns a pair 1154 * of iterators. The first iterator points into the first range, the 1155 * second iterator points into the second range, and the elements pointed 1156 * to by the iterators are not equal. 1157 */ 1158 template<typename _InputIterator1, typename _InputIterator2> 1159 pair<_InputIterator1, _InputIterator2> 1160 mismatch(_InputIterator1 __first1, _InputIterator1 __last1, 1161 _InputIterator2 __first2) 1162 { 1163 // concept requirements 1164 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) 1165 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) 1166 __glibcxx_function_requires(_EqualOpConcept< 1167 typename iterator_traits<_InputIterator1>::value_type, 1168 typename iterator_traits<_InputIterator2>::value_type>) 1169 __glibcxx_requires_valid_range(__first1, __last1); 1170 1171 while (__first1 != __last1 && *__first1 == *__first2) 1172 { 1173 ++__first1; 1174 ++__first2; 1175 } 1176 return pair<_InputIterator1, _InputIterator2>(__first1, __first2); 1177 } 1178 1179 /** 1180 * @brief Finds the places in ranges which don't match. 1181 * @ingroup non_mutating_algorithms 1182 * @param __first1 An input iterator. 1183 * @param __last1 An input iterator. 1184 * @param __first2 An input iterator. 1185 * @param __binary_pred A binary predicate @link functors 1186 * functor@endlink. 1187 * @return A pair of iterators pointing to the first mismatch. 1188 * 1189 * This compares the elements of two ranges using the binary_pred 1190 * parameter, and returns a pair 1191 * of iterators. The first iterator points into the first range, the 1192 * second iterator points into the second range, and the elements pointed 1193 * to by the iterators are not equal. 1194 */ 1195 template<typename _InputIterator1, typename _InputIterator2, 1196 typename _BinaryPredicate> 1197 pair<_InputIterator1, _InputIterator2> 1198 mismatch(_InputIterator1 __first1, _InputIterator1 __last1, 1199 _InputIterator2 __first2, _BinaryPredicate __binary_pred) 1200 { 1201 // concept requirements 1202 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) 1203 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) 1204 __glibcxx_requires_valid_range(__first1, __last1); 1205 1206 while (__first1 != __last1 && bool(__binary_pred(*__first1, *__first2))) 1207 { 1208 ++__first1; 1209 ++__first2; 1210 } 1211 return pair<_InputIterator1, _InputIterator2>(__first1, __first2); 1212 } 1213 1214 _GLIBCXX_END_NAMESPACE_ALGO 1215 } // namespace std 1216 1217 // NB: This file is included within many other C++ includes, as a way 1218 // of getting the base algorithms. So, make sure that parallel bits 1219 // come in too if requested. 1220 #ifdef _GLIBCXX_PARALLEL 1221 # include <parallel/algobase.h> 1222 #endif 1223 1224 #endif 1225
