1 // Core algorithmic facilities -*- C++ -*- 2 3 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 4 // Free Software Foundation, Inc. 5 // 6 // This file is part of the GNU ISO C++ Library. This library is free 7 // software; you can redistribute it and/or modify it under the 8 // terms of the GNU General Public License as published by the 9 // Free Software Foundation; either version 3, or (at your option) 10 // any later version. 11 12 // This library is distributed in the hope that it will be useful, 13 // but WITHOUT ANY WARRANTY; without even the implied warranty of 14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 // GNU General Public License for more details. 16 17 // Under Section 7 of GPL version 3, you are granted additional 18 // permissions described in the GCC Runtime Library Exception, version 19 // 3.1, as published by the Free Software Foundation. 20 21 // You should have received a copy of the GNU General Public License and 22 // a copy of the GCC Runtime Library Exception along with this program; 23 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 24 // <http://www.gnu.org/licenses/>. 25 26 /* 27 * 28 * Copyright (c) 1994 29 * Hewlett-Packard Company 30 * 31 * Permission to use, copy, modify, distribute and sell this software 32 * and its documentation for any purpose is hereby granted without fee, 33 * provided that the above copyright notice appear in all copies and 34 * that both that copyright notice and this permission notice appear 35 * in supporting documentation. Hewlett-Packard Company makes no 36 * representations about the suitability of this software for any 37 * purpose. It is provided "as is" without express or implied warranty. 38 * 39 * 40 * Copyright (c) 1996-1998 41 * Silicon Graphics Computer Systems, Inc. 42 * 43 * Permission to use, copy, modify, distribute and sell this software 44 * and its documentation for any purpose is hereby granted without fee, 45 * provided that the above copyright notice appear in all copies and 46 * that both that copyright notice and this permission notice appear 47 * in supporting documentation. Silicon Graphics makes no 48 * representations about the suitability of this software for any 49 * purpose. It is provided "as is" without express or implied warranty. 50 */ 51 52 /** @file stl_algobase.h 53 * This is an internal header file, included by other library headers. 54 * You should not attempt to use it directly. 55 */ 56 57 #ifndef _STL_ALGOBASE_H 58 #define _STL_ALGOBASE_H 1 59 60 #include <bits/c++config.h> 61 #include <cstddef> 62 #include <bits/functexcept.h> 63 #include <bits/cpp_type_traits.h> 64 #include <ext/type_traits.h> 65 #include <ext/numeric_traits.h> 66 #include <bits/stl_pair.h> 67 #include <bits/stl_iterator_base_types.h> 68 #include <bits/stl_iterator_base_funcs.h> 69 #include <bits/stl_iterator.h> 70 #include <bits/concept_check.h> 71 #include <debug/debug.h> 72 #include <bits/move.h> // For std::swap and _GLIBCXX_MOVE 73 74 _GLIBCXX_BEGIN_NAMESPACE(std) 75 76 // See http://gcc.gnu.org/ml/libstdc++/2004-08/msg00167.html: in a 77 // nutshell, we are partially implementing the resolution of DR 187, 78 // when it's safe, i.e., the value_types are equal. 79 template<bool _BoolType> 80 struct __iter_swap 81 { 82 template<typename _ForwardIterator1, typename _ForwardIterator2> 83 static void 84 iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b) 85 { 86 typedef typename iterator_traits<_ForwardIterator1>::value_type 87 _ValueType1; 88 _ValueType1 __tmp = _GLIBCXX_MOVE(*__a); 89 *__a = _GLIBCXX_MOVE(*__b); 90 *__b = _GLIBCXX_MOVE(__tmp); 91 } 92 }; 93 94 template<> 95 struct __iter_swap<true> 96 { 97 template<typename _ForwardIterator1, typename _ForwardIterator2> 98 static void 99 iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b) 100 { 101 swap(*__a, *__b); 102 } 103 }; 104 105 /** 106 * @brief Swaps the contents of two iterators. 107 * @ingroup mutating_algorithms 108 * @param a An iterator. 109 * @param b Another iterator. 110 * @return Nothing. 111 * 112 * This function swaps the values pointed to by two iterators, not the 113 * iterators themselves. 114 */ 115 template<typename _ForwardIterator1, typename _ForwardIterator2> 116 inline void 117 iter_swap(_ForwardIterator1 __a, _ForwardIterator2 __b) 118 { 119 typedef typename iterator_traits<_ForwardIterator1>::value_type 120 _ValueType1; 121 typedef typename iterator_traits<_ForwardIterator2>::value_type 122 _ValueType2; 123 124 // concept requirements 125 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< 126 _ForwardIterator1>) 127 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< 128 _ForwardIterator2>) 129 __glibcxx_function_requires(_ConvertibleConcept<_ValueType1, 130 _ValueType2>) 131 __glibcxx_function_requires(_ConvertibleConcept<_ValueType2, 132 _ValueType1>) 133 134 typedef typename iterator_traits<_ForwardIterator1>::reference 135 _ReferenceType1; 136 typedef typename iterator_traits<_ForwardIterator2>::reference 137 _ReferenceType2; 138 std::__iter_swap<__are_same<_ValueType1, _ValueType2>::__value 139 && __are_same<_ValueType1&, _ReferenceType1>::__value 140 && __are_same<_ValueType2&, _ReferenceType2>::__value>:: 141 iter_swap(__a, __b); 142 } 143 144 /** 145 * @brief Swap the elements of two sequences. 146 * @ingroup mutating_algorithms 147 * @param first1 A forward iterator. 148 * @param last1 A forward iterator. 149 * @param first2 A forward iterator. 150 * @return An iterator equal to @p first2+(last1-first1). 151 * 152 * Swaps each element in the range @p [first1,last1) with the 153 * corresponding element in the range @p [first2,(last1-first1)). 154 * The ranges must not overlap. 155 */ 156 template<typename _ForwardIterator1, typename _ForwardIterator2> 157 _ForwardIterator2 158 swap_ranges(_ForwardIterator1 __first1, _ForwardIterator1 __last1, 159 _ForwardIterator2 __first2) 160 { 161 // concept requirements 162 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< 163 _ForwardIterator1>) 164 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< 165 _ForwardIterator2>) 166 __glibcxx_requires_valid_range(__first1, __last1); 167 168 for (; __first1 != __last1; ++__first1, ++__first2) 169 std::iter_swap(__first1, __first2); 170 return __first2; 171 } 172 173 /** 174 * @brief This does what you think it does. 175 * @ingroup sorting_algorithms 176 * @param a A thing of arbitrary type. 177 * @param b Another thing of arbitrary type. 178 * @return The lesser of the parameters. 179 * 180 * This is the simple classic generic implementation. It will work on 181 * temporary expressions, since they are only evaluated once, unlike a 182 * preprocessor macro. 183 */ 184 template<typename _Tp> 185 inline const _Tp& 186 min(const _Tp& __a, const _Tp& __b) 187 { 188 // concept requirements 189 __glibcxx_function_requires(_LessThanComparableConcept<_Tp>) 190 //return __b < __a ? __b : __a; 191 if (__b < __a) 192 return __b; 193 return __a; 194 } 195 196 /** 197 * @brief This does what you think it does. 198 * @ingroup sorting_algorithms 199 * @param a A thing of arbitrary type. 200 * @param b Another thing of arbitrary type. 201 * @return The greater of the parameters. 202 * 203 * This is the simple classic generic implementation. It will work on 204 * temporary expressions, since they are only evaluated once, unlike a 205 * preprocessor macro. 206 */ 207 template<typename _Tp> 208 inline const _Tp& 209 max(const _Tp& __a, const _Tp& __b) 210 { 211 // concept requirements 212 __glibcxx_function_requires(_LessThanComparableConcept<_Tp>) 213 //return __a < __b ? __b : __a; 214 if (__a < __b) 215 return __b; 216 return __a; 217 } 218 219 /** 220 * @brief This does what you think it does. 221 * @ingroup sorting_algorithms 222 * @param a A thing of arbitrary type. 223 * @param b Another thing of arbitrary type. 224 * @param comp A @link comparison_functors comparison functor@endlink. 225 * @return The lesser of the parameters. 226 * 227 * This will work on temporary expressions, since they are only evaluated 228 * once, unlike a preprocessor macro. 229 */ 230 template<typename _Tp, typename _Compare> 231 inline const _Tp& 232 min(const _Tp& __a, const _Tp& __b, _Compare __comp) 233 { 234 //return __comp(__b, __a) ? __b : __a; 235 if (__comp(__b, __a)) 236 return __b; 237 return __a; 238 } 239 240 /** 241 * @brief This does what you think it does. 242 * @ingroup sorting_algorithms 243 * @param a A thing of arbitrary type. 244 * @param b Another thing of arbitrary type. 245 * @param comp A @link comparison_functors comparison functor@endlink. 246 * @return The greater of the parameters. 247 * 248 * This will work on temporary expressions, since they are only evaluated 249 * once, unlike a preprocessor macro. 250 */ 251 template<typename _Tp, typename _Compare> 252 inline const _Tp& 253 max(const _Tp& __a, const _Tp& __b, _Compare __comp) 254 { 255 //return __comp(__a, __b) ? __b : __a; 256 if (__comp(__a, __b)) 257 return __b; 258 return __a; 259 } 260 261 262 // If _Iterator has a base returns it otherwise _Iterator is returned 263 // untouched 264 template<typename _Iterator, bool _HasBase> 265 struct _Iter_base 266 { 267 typedef _Iterator iterator_type; 268 static iterator_type 269 _S_base(_Iterator __it) 270 { return __it; } 271 }; 272 273 template<typename _Iterator> 274 struct _Iter_base<_Iterator, true> 275 { 276 typedef typename _Iterator::iterator_type iterator_type; 277 static iterator_type 278 _S_base(_Iterator __it) 279 { return __it.base(); } 280 }; 281 282 // If _Iterator is a __normal_iterator return its base (a plain pointer, 283 // normally) otherwise return it untouched. See copy, fill, ... 284 template<typename _Iterator> 285 struct _Niter_base 286 : _Iter_base<_Iterator, __is_normal_iterator<_Iterator>::__value> 287 { }; 288 289 template<typename _Iterator> 290 inline typename _Niter_base<_Iterator>::iterator_type 291 __niter_base(_Iterator __it) 292 { return std::_Niter_base<_Iterator>::_S_base(__it); } 293 294 // Likewise, for move_iterator. 295 template<typename _Iterator> 296 struct _Miter_base 297 : _Iter_base<_Iterator, __is_move_iterator<_Iterator>::__value> 298 { }; 299 300 template<typename _Iterator> 301 inline typename _Miter_base<_Iterator>::iterator_type 302 __miter_base(_Iterator __it) 303 { return std::_Miter_base<_Iterator>::_S_base(__it); } 304 305 // All of these auxiliary structs serve two purposes. (1) Replace 306 // calls to copy with memmove whenever possible. (Memmove, not memcpy, 307 // because the input and output ranges are permitted to overlap.) 308 // (2) If we're using random access iterators, then write the loop as 309 // a for loop with an explicit count. 310 311 template<bool, bool, typename> 312 struct __copy_move 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 = *__first; 320 return __result; 321 } 322 }; 323 324 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 325 template<typename _Category> 326 struct __copy_move<true, false, _Category> 327 { 328 template<typename _II, typename _OI> 329 static _OI 330 __copy_m(_II __first, _II __last, _OI __result) 331 { 332 for (; __first != __last; ++__result, ++__first) 333 *__result = std::move(*__first); 334 return __result; 335 } 336 }; 337 #endif 338 339 template<> 340 struct __copy_move<false, false, random_access_iterator_tag> 341 { 342 template<typename _II, typename _OI> 343 static _OI 344 __copy_m(_II __first, _II __last, _OI __result) 345 { 346 typedef typename iterator_traits<_II>::difference_type _Distance; 347 for(_Distance __n = __last - __first; __n > 0; --__n) 348 { 349 *__result = *__first; 350 ++__first; 351 ++__result; 352 } 353 return __result; 354 } 355 }; 356 357 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 358 template<> 359 struct __copy_move<true, false, random_access_iterator_tag> 360 { 361 template<typename _II, typename _OI> 362 static _OI 363 __copy_m(_II __first, _II __last, _OI __result) 364 { 365 typedef typename iterator_traits<_II>::difference_type _Distance; 366 for(_Distance __n = __last - __first; __n > 0; --__n) 367 { 368 *__result = std::move(*__first); 369 ++__first; 370 ++__result; 371 } 372 return __result; 373 } 374 }; 375 #endif 376 377 template<bool _IsMove> 378 struct __copy_move<_IsMove, true, random_access_iterator_tag> 379 { 380 template<typename _Tp> 381 static _Tp* 382 __copy_m(const _Tp* __first, const _Tp* __last, _Tp* __result) 383 { 384 const ptrdiff_t _Num = __last - __first; 385 if (_Num) 386 __builtin_memmove(__result, __first, sizeof(_Tp) * _Num); 387 return __result + _Num; 388 } 389 }; 390 391 template<bool _IsMove, typename _II, typename _OI> 392 inline _OI 393 __copy_move_a(_II __first, _II __last, _OI __result) 394 { 395 typedef typename iterator_traits<_II>::value_type _ValueTypeI; 396 typedef typename iterator_traits<_OI>::value_type _ValueTypeO; 397 typedef typename iterator_traits<_II>::iterator_category _Category; 398 const bool __simple = (__is_pod(_ValueTypeI) 399 && __is_pointer<_II>::__value 400 && __is_pointer<_OI>::__value 401 && __are_same<_ValueTypeI, _ValueTypeO>::__value); 402 403 return std::__copy_move<_IsMove, __simple, 404 _Category>::__copy_m(__first, __last, __result); 405 } 406 407 // Helpers for streambuf iterators (either istream or ostream). 408 // NB: avoid including <iosfwd>, relatively large. 409 template<typename _CharT> 410 struct char_traits; 411 412 template<typename _CharT, typename _Traits> 413 class istreambuf_iterator; 414 415 template<typename _CharT, typename _Traits> 416 class ostreambuf_iterator; 417 418 template<bool _IsMove, typename _CharT> 419 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 420 ostreambuf_iterator<_CharT, char_traits<_CharT> > >::__type 421 __copy_move_a2(_CharT*, _CharT*, 422 ostreambuf_iterator<_CharT, char_traits<_CharT> >); 423 424 template<bool _IsMove, typename _CharT> 425 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 426 ostreambuf_iterator<_CharT, char_traits<_CharT> > >::__type 427 __copy_move_a2(const _CharT*, const _CharT*, 428 ostreambuf_iterator<_CharT, char_traits<_CharT> >); 429 430 template<bool _IsMove, typename _CharT> 431 typename __gnu_cxx::__enable_if<__is_char<_CharT>::__value, 432 _CharT*>::__type 433 __copy_move_a2(istreambuf_iterator<_CharT, char_traits<_CharT> >, 434 istreambuf_iterator<_CharT, char_traits<_CharT> >, _CharT*); 435 436 template<bool _IsMove, typename _II, typename _OI> 437 inline _OI 438 __copy_move_a2(_II __first, _II __last, _OI __result) 439 { 440 return _OI(std::__copy_move_a<_IsMove>(std::__niter_base(__first), 441 std::__niter_base(__last), 442 std::__niter_base(__result))); 443 } 444 445 /** 446 * @brief Copies the range [first,last) into result. 447 * @ingroup mutating_algorithms 448 * @param first An input iterator. 449 * @param last An input iterator. 450 * @param result An output iterator. 451 * @return result + (first - last) 452 * 453 * This inline function will boil down to a call to @c memmove whenever 454 * possible. Failing that, if random access iterators are passed, then the 455 * loop count will be known (and therefore a candidate for compiler 456 * optimizations such as unrolling). Result may not be contained within 457 * [first,last); the copy_backward function should be used instead. 458 * 459 * Note that the end of the output range is permitted to be contained 460 * within [first,last). 461 */ 462 template<typename _II, typename _OI> 463 inline _OI 464 copy(_II __first, _II __last, _OI __result) 465 { 466 // concept requirements 467 __glibcxx_function_requires(_InputIteratorConcept<_II>) 468 __glibcxx_function_requires(_OutputIteratorConcept<_OI, 469 typename iterator_traits<_II>::value_type>) 470 __glibcxx_requires_valid_range(__first, __last); 471 472 return (std::__copy_move_a2<__is_move_iterator<_II>::__value> 473 (std::__miter_base(__first), std::__miter_base(__last), 474 __result)); 475 } 476 477 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 478 /** 479 * @brief Moves the range [first,last) into result. 480 * @ingroup mutating_algorithms 481 * @param first An input iterator. 482 * @param last An input iterator. 483 * @param result An output iterator. 484 * @return result + (first - last) 485 * 486 * This inline function will boil down to a call to @c memmove whenever 487 * possible. Failing that, if random access iterators are passed, then the 488 * loop count will be known (and therefore a candidate for compiler 489 * optimizations such as unrolling). Result may not be contained within 490 * [first,last); the move_backward function should be used instead. 491 * 492 * Note that the end of the output range is permitted to be contained 493 * within [first,last). 494 */ 495 template<typename _II, typename _OI> 496 inline _OI 497 move(_II __first, _II __last, _OI __result) 498 { 499 // concept requirements 500 __glibcxx_function_requires(_InputIteratorConcept<_II>) 501 __glibcxx_function_requires(_OutputIteratorConcept<_OI, 502 typename iterator_traits<_II>::value_type>) 503 __glibcxx_requires_valid_range(__first, __last); 504 505 return std::__copy_move_a2<true>(std::__miter_base(__first), 506 std::__miter_base(__last), __result); 507 } 508 509 #define _GLIBCXX_MOVE3(_Tp, _Up, _Vp) std::move(_Tp, _Up, _Vp) 510 #else 511 #define _GLIBCXX_MOVE3(_Tp, _Up, _Vp) std::copy(_Tp, _Up, _Vp) 512 #endif 513 514 template<bool, bool, typename> 515 struct __copy_move_backward 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 = *--__last; 523 return __result; 524 } 525 }; 526 527 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 528 template<typename _Category> 529 struct __copy_move_backward<true, false, _Category> 530 { 531 template<typename _BI1, typename _BI2> 532 static _BI2 533 __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result) 534 { 535 while (__first != __last) 536 *--__result = std::move(*--__last); 537 return __result; 538 } 539 }; 540 #endif 541 542 template<> 543 struct __copy_move_backward<false, false, random_access_iterator_tag> 544 { 545 template<typename _BI1, typename _BI2> 546 static _BI2 547 __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result) 548 { 549 typename iterator_traits<_BI1>::difference_type __n; 550 for (__n = __last - __first; __n > 0; --__n) 551 *--__result = *--__last; 552 return __result; 553 } 554 }; 555 556 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 557 template<> 558 struct __copy_move_backward<true, false, random_access_iterator_tag> 559 { 560 template<typename _BI1, typename _BI2> 561 static _BI2 562 __copy_move_b(_BI1 __first, _BI1 __last, _BI2 __result) 563 { 564 typename iterator_traits<_BI1>::difference_type __n; 565 for (__n = __last - __first; __n > 0; --__n) 566 *--__result = std::move(*--__last); 567 return __result; 568 } 569 }; 570 #endif 571 572 template<bool _IsMove> 573 struct __copy_move_backward<_IsMove, true, random_access_iterator_tag> 574 { 575 template<typename _Tp> 576 static _Tp* 577 __copy_move_b(const _Tp* __first, const _Tp* __last, _Tp* __result) 578 { 579 const ptrdiff_t _Num = __last - __first; 580 if (_Num) 581 __builtin_memmove(__result - _Num, __first, sizeof(_Tp) * _Num); 582 return __result - _Num; 583 } 584 }; 585 586 template<bool _IsMove, typename _BI1, typename _BI2> 587 inline _BI2 588 __copy_move_backward_a(_BI1 __first, _BI1 __last, _BI2 __result) 589 { 590 typedef typename iterator_traits<_BI1>::value_type _ValueType1; 591 typedef typename iterator_traits<_BI2>::value_type _ValueType2; 592 typedef typename iterator_traits<_BI1>::iterator_category _Category; 593 const bool __simple = (__is_pod(_ValueType1) 594 && __is_pointer<_BI1>::__value 595 && __is_pointer<_BI2>::__value 596 && __are_same<_ValueType1, _ValueType2>::__value); 597 598 return std::__copy_move_backward<_IsMove, __simple, 599 _Category>::__copy_move_b(__first, 600 __last, 601 __result); 602 } 603 604 template<bool _IsMove, typename _BI1, typename _BI2> 605 inline _BI2 606 __copy_move_backward_a2(_BI1 __first, _BI1 __last, _BI2 __result) 607 { 608 return _BI2(std::__copy_move_backward_a<_IsMove> 609 (std::__niter_base(__first), std::__niter_base(__last), 610 std::__niter_base(__result))); 611 } 612 613 /** 614 * @brief Copies the range [first,last) into result. 615 * @ingroup mutating_algorithms 616 * @param first A bidirectional iterator. 617 * @param last A bidirectional iterator. 618 * @param result A bidirectional iterator. 619 * @return result - (first - last) 620 * 621 * The function has the same effect as copy, but starts at the end of the 622 * range and works its way to the start, returning the start of the result. 623 * This inline function will boil down to a call to @c memmove whenever 624 * possible. Failing that, if random access iterators are passed, then the 625 * loop count will be known (and therefore a candidate for compiler 626 * optimizations such as unrolling). 627 * 628 * Result may not be in the range [first,last). Use copy instead. Note 629 * that the start of the output range may overlap [first,last). 630 */ 631 template<typename _BI1, typename _BI2> 632 inline _BI2 633 copy_backward(_BI1 __first, _BI1 __last, _BI2 __result) 634 { 635 // concept requirements 636 __glibcxx_function_requires(_BidirectionalIteratorConcept<_BI1>) 637 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<_BI2>) 638 __glibcxx_function_requires(_ConvertibleConcept< 639 typename iterator_traits<_BI1>::value_type, 640 typename iterator_traits<_BI2>::value_type>) 641 __glibcxx_requires_valid_range(__first, __last); 642 643 return (std::__copy_move_backward_a2<__is_move_iterator<_BI1>::__value> 644 (std::__miter_base(__first), std::__miter_base(__last), 645 __result)); 646 } 647 648 #ifdef __GXX_EXPERIMENTAL_CXX0X__ 649 /** 650 * @brief Moves the range [first,last) into result. 651 * @ingroup mutating_algorithms 652 * @param first A bidirectional iterator. 653 * @param last A bidirectional iterator. 654 * @param result A bidirectional iterator. 655 * @return result - (first - last) 656 * 657 * The function has the same effect as move, but starts at the end of the 658 * range and works its way to the start, returning the start of the result. 659 * This inline function will boil down to a call to @c memmove whenever 660 * possible. Failing that, if random access iterators are passed, then the 661 * loop count will be known (and therefore a candidate for compiler 662 * optimizations such as unrolling). 663 * 664 * Result may not be in the range [first,last). Use move instead. Note 665 * that the start of the output range may overlap [first,last). 666 */ 667 template<typename _BI1, typename _BI2> 668 inline _BI2 669 move_backward(_BI1 __first, _BI1 __last, _BI2 __result) 670 { 671 // concept requirements 672 __glibcxx_function_requires(_BidirectionalIteratorConcept<_BI1>) 673 __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<_BI2>) 674 __glibcxx_function_requires(_ConvertibleConcept< 675 typename iterator_traits<_BI1>::value_type, 676 typename iterator_traits<_BI2>::value_type>) 677 __glibcxx_requires_valid_range(__first, __last); 678 679 return std::__copy_move_backward_a2<true>(std::__miter_base(__first), 680 std::__miter_base(__last), 681 __result); 682 } 683 684 #define _GLIBCXX_MOVE_BACKWARD3(_Tp, _Up, _Vp) std::move_backward(_Tp, _Up, _Vp) 685 #else 686 #define _GLIBCXX_MOVE_BACKWARD3(_Tp, _Up, _Vp) std::copy_backward(_Tp, _Up, _Vp) 687 #endif 688 689 template<typename _ForwardIterator, typename _Tp> 690 inline typename 691 __gnu_cxx::__enable_if<!__is_scalar<_Tp>::__value, void>::__type 692 __fill_a(_ForwardIterator __first, _ForwardIterator __last, 693 const _Tp& __value) 694 { 695 for (; __first != __last; ++__first) 696 *__first = __value; 697 } 698 699 template<typename _ForwardIterator, typename _Tp> 700 inline typename 701 __gnu_cxx::__enable_if<__is_scalar<_Tp>::__value, void>::__type 702 __fill_a(_ForwardIterator __first, _ForwardIterator __last, 703 const _Tp& __value) 704 { 705 const _Tp __tmp = __value; 706 for (; __first != __last; ++__first) 707 *__first = __tmp; 708 } 709 710 // Specialization: for char types we can use memset. 711 template<typename _Tp> 712 inline typename 713 __gnu_cxx::__enable_if<__is_byte<_Tp>::__value, void>::__type 714 __fill_a(_Tp* __first, _Tp* __last, const _Tp& __c) 715 { 716 const _Tp __tmp = __c; 717 __builtin_memset(__first, static_cast<unsigned char>(__tmp), 718 __last - __first); 719 } 720 721 /** 722 * @brief Fills the range [first,last) with copies of value. 723 * @ingroup mutating_algorithms 724 * @param first A forward iterator. 725 * @param last A forward iterator. 726 * @param value A reference-to-const of arbitrary type. 727 * @return Nothing. 728 * 729 * This function fills a range with copies of the same value. For char 730 * types filling contiguous areas of memory, this becomes an inline call 731 * to @c memset or @c wmemset. 732 */ 733 template<typename _ForwardIterator, typename _Tp> 734 inline void 735 fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) 736 { 737 // concept requirements 738 __glibcxx_function_requires(_Mutable_ForwardIteratorConcept< 739 _ForwardIterator>) 740 __glibcxx_requires_valid_range(__first, __last); 741 742 std::__fill_a(std::__niter_base(__first), std::__niter_base(__last), 743 __value); 744 } 745 746 template<typename _OutputIterator, typename _Size, typename _Tp> 747 inline typename 748 __gnu_cxx::__enable_if<!__is_scalar<_Tp>::__value, _OutputIterator>::__type 749 __fill_n_a(_OutputIterator __first, _Size __n, const _Tp& __value) 750 { 751 for (; __n > 0; --__n, ++__first) 752 *__first = __value; 753 return __first; 754 } 755 756 template<typename _OutputIterator, typename _Size, typename _Tp> 757 inline typename 758 __gnu_cxx::__enable_if<__is_scalar<_Tp>::__value, _OutputIterator>::__type 759 __fill_n_a(_OutputIterator __first, _Size __n, const _Tp& __value) 760 { 761 const _Tp __tmp = __value; 762 for (; __n > 0; --__n, ++__first) 763 *__first = __tmp; 764 return __first; 765 } 766 767 template<typename _Size, typename _Tp> 768 inline typename 769 __gnu_cxx::__enable_if<__is_byte<_Tp>::__value, _Tp*>::__type 770 __fill_n_a(_Tp* __first, _Size __n, const _Tp& __c) 771 { 772 std::__fill_a(__first, __first + __n, __c); 773 return __first + __n; 774 } 775 776 /** 777 * @brief Fills the range [first,first+n) with copies of value. 778 * @ingroup mutating_algorithms 779 * @param first An output iterator. 780 * @param n The count of copies to perform. 781 * @param value A reference-to-const of arbitrary type. 782 * @return The iterator at first+n. 783 * 784 * This function fills a range with copies of the same value. For char 785 * types filling contiguous areas of memory, this becomes an inline call 786 * to @c memset or @ wmemset. 787 * 788 * _GLIBCXX_RESOLVE_LIB_DEFECTS 789 * DR 865. More algorithms that throw away information 790 */ 791 template<typename _OI, typename _Size, typename _Tp> 792 inline _OI 793 fill_n(_OI __first, _Size __n, const _Tp& __value) 794 { 795 // concept requirements 796 __glibcxx_function_requires(_OutputIteratorConcept<_OI, _Tp>) 797 798 return _OI(std::__fill_n_a(std::__niter_base(__first), __n, __value)); 799 } 800 801 template<bool _BoolType> 802 struct __equal 803 { 804 template<typename _II1, typename _II2> 805 static bool 806 equal(_II1 __first1, _II1 __last1, _II2 __first2) 807 { 808 for (; __first1 != __last1; ++__first1, ++__first2) 809 if (!(*__first1 == *__first2)) 810 return false; 811 return true; 812 } 813 }; 814 815 template<> 816 struct __equal<true> 817 { 818 template<typename _Tp> 819 static bool 820 equal(const _Tp* __first1, const _Tp* __last1, const _Tp* __first2) 821 { 822 return !__builtin_memcmp(__first1, __first2, sizeof(_Tp) 823 * (__last1 - __first1)); 824 } 825 }; 826 827 template<typename _II1, typename _II2> 828 inline bool 829 __equal_aux(_II1 __first1, _II1 __last1, _II2 __first2) 830 { 831 typedef typename iterator_traits<_II1>::value_type _ValueType1; 832 typedef typename iterator_traits<_II2>::value_type _ValueType2; 833 const bool __simple = (__is_integer<_ValueType1>::__value 834 && __is_pointer<_II1>::__value 835 && __is_pointer<_II2>::__value 836 && __are_same<_ValueType1, _ValueType2>::__value); 837 838 return std::__equal<__simple>::equal(__first1, __last1, __first2); 839 } 840 841 842 template<typename, typename> 843 struct __lc_rai 844 { 845 template<typename _II1, typename _II2> 846 static _II1 847 __newlast1(_II1, _II1 __last1, _II2, _II2) 848 { return __last1; } 849 850 template<typename _II> 851 static bool 852 __cnd2(_II __first, _II __last) 853 { return __first != __last; } 854 }; 855 856 template<> 857 struct __lc_rai<random_access_iterator_tag, random_access_iterator_tag> 858 { 859 template<typename _RAI1, typename _RAI2> 860 static _RAI1 861 __newlast1(_RAI1 __first1, _RAI1 __last1, 862 _RAI2 __first2, _RAI2 __last2) 863 { 864 const typename iterator_traits<_RAI1>::difference_type 865 __diff1 = __last1 - __first1; 866 const typename iterator_traits<_RAI2>::difference_type 867 __diff2 = __last2 - __first2; 868 return __diff2 < __diff1 ? __first1 + __diff2 : __last1; 869 } 870 871 template<typename _RAI> 872 static bool 873 __cnd2(_RAI, _RAI) 874 { return true; } 875 }; 876 877 template<bool _BoolType> 878 struct __lexicographical_compare 879 { 880 template<typename _II1, typename _II2> 881 static bool __lc(_II1, _II1, _II2, _II2); 882 }; 883 884 template<bool _BoolType> 885 template<typename _II1, typename _II2> 886 bool 887 __lexicographical_compare<_BoolType>:: 888 __lc(_II1 __first1, _II1 __last1, _II2 __first2, _II2 __last2) 889 { 890 typedef typename iterator_traits<_II1>::iterator_category _Category1; 891 typedef typename iterator_traits<_II2>::iterator_category _Category2; 892 typedef std::__lc_rai<_Category1, _Category2> __rai_type; 893 894 __last1 = __rai_type::__newlast1(__first1, __last1, 895 __first2, __last2); 896 for (; __first1 != __last1 && __rai_type::__cnd2(__first2, __last2); 897 ++__first1, ++__first2) 898 { 899 if (*__first1 < *__first2) 900 return true; 901 if (*__first2 < *__first1) 902 return false; 903 } 904 return __first1 == __last1 && __first2 != __last2; 905 } 906 907 template<> 908 struct __lexicographical_compare<true> 909 { 910 template<typename _Tp, typename _Up> 911 static bool 912 __lc(const _Tp* __first1, const _Tp* __last1, 913 const _Up* __first2, const _Up* __last2) 914 { 915 const size_t __len1 = __last1 - __first1; 916 const size_t __len2 = __last2 - __first2; 917 const int __result = __builtin_memcmp(__first1, __first2, 918 std::min(__len1, __len2)); 919 return __result != 0 ? __result < 0 : __len1 < __len2; 920 } 921 }; 922 923 template<typename _II1, typename _II2> 924 inline bool 925 __lexicographical_compare_aux(_II1 __first1, _II1 __last1, 926 _II2 __first2, _II2 __last2) 927 { 928 typedef typename iterator_traits<_II1>::value_type _ValueType1; 929 typedef typename iterator_traits<_II2>::value_type _ValueType2; 930 const bool __simple = 931 (__is_byte<_ValueType1>::__value && __is_byte<_ValueType2>::__value 932 && !__gnu_cxx::__numeric_traits<_ValueType1>::__is_signed_val 933 && !__gnu_cxx::__numeric_traits<_ValueType2>::__is_signed_val 934 && __is_pointer<_II1>::__value 935 && __is_pointer<_II2>::__value); 936 937 return std::__lexicographical_compare<__simple>::__lc(__first1, __last1, 938 __first2, __last2); 939 } 940 941 /** 942 * @brief Finds the first position in which @a val could be inserted 943 * without changing the ordering. 944 * @param first An iterator. 945 * @param last Another iterator. 946 * @param val The search term. 947 * @return An iterator pointing to the first element <em>not less 948 * than</em> @a val, or end() if every element is less than 949 * @a val. 950 * @ingroup binary_search_algorithms 951 */ 952 template<typename _ForwardIterator, typename _Tp> 953 _ForwardIterator 954 lower_bound(_ForwardIterator __first, _ForwardIterator __last, 955 const _Tp& __val) 956 { 957 typedef typename iterator_traits<_ForwardIterator>::value_type 958 _ValueType; 959 typedef typename iterator_traits<_ForwardIterator>::difference_type 960 _DistanceType; 961 962 // concept requirements 963 __glibcxx_function_requires(_ForwardIteratorConcept<_ForwardIterator>) 964 __glibcxx_function_requires(_LessThanOpConcept<_ValueType, _Tp>) 965 __glibcxx_requires_partitioned_lower(__first, __last, __val); 966 967 _DistanceType __len = std::distance(__first, __last); 968 _DistanceType __half; 969 _ForwardIterator __middle; 970 971 while (__len > 0) 972 { 973 __half = __len >> 1; 974 __middle = __first; 975 std::advance(__middle, __half); 976 if (*__middle < __val) 977 { 978 __first = __middle; 979 ++__first; 980 __len = __len - __half - 1; 981 } 982 else 983 __len = __half; 984 } 985 return __first; 986 } 987 988 /// This is a helper function for the sort routines and for random.tcc. 989 // Precondition: __n > 0. 990 template<typename _Size> 991 inline _Size 992 __lg(_Size __n) 993 { 994 _Size __k; 995 for (__k = 0; __n != 0; __n >>= 1) 996 ++__k; 997 return __k - 1; 998 } 999 1000 inline int 1001 __lg(int __n) 1002 { return sizeof(int) * __CHAR_BIT__ - 1 - __builtin_clz(__n); } 1003 1004 inline long 1005 __lg(long __n) 1006 { return sizeof(long) * __CHAR_BIT__ - 1 - __builtin_clzl(__n); } 1007 1008 inline long long 1009 __lg(long long __n) 1010 { return sizeof(long long) * __CHAR_BIT__ - 1 - __builtin_clzll(__n); } 1011 1012 _GLIBCXX_END_NAMESPACE 1013 1014 _GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD_P) 1015 1016 /** 1017 * @brief Tests a range for element-wise equality. 1018 * @ingroup non_mutating_algorithms 1019 * @param first1 An input iterator. 1020 * @param last1 An input iterator. 1021 * @param first2 An input iterator. 1022 * @return A boolean true or false. 1023 * 1024 * This compares the elements of two ranges using @c == and returns true or 1025 * false depending on whether all of the corresponding elements of the 1026 * ranges are equal. 1027 */ 1028 template<typename _II1, typename _II2> 1029 inline bool 1030 equal(_II1 __first1, _II1 __last1, _II2 __first2) 1031 { 1032 // concept requirements 1033 __glibcxx_function_requires(_InputIteratorConcept<_II1>) 1034 __glibcxx_function_requires(_InputIteratorConcept<_II2>) 1035 __glibcxx_function_requires(_EqualOpConcept< 1036 typename iterator_traits<_II1>::value_type, 1037 typename iterator_traits<_II2>::value_type>) 1038 __glibcxx_requires_valid_range(__first1, __last1); 1039 1040 return std::__equal_aux(std::__niter_base(__first1), 1041 std::__niter_base(__last1), 1042 std::__niter_base(__first2)); 1043 } 1044 1045 /** 1046 * @brief Tests a range for element-wise equality. 1047 * @ingroup non_mutating_algorithms 1048 * @param first1 An input iterator. 1049 * @param last1 An input iterator. 1050 * @param first2 An input iterator. 1051 * @param binary_pred A binary predicate @link functors 1052 * functor@endlink. 1053 * @return A boolean true or false. 1054 * 1055 * This compares the elements of two ranges using the binary_pred 1056 * parameter, and returns true or 1057 * false depending on whether all of the corresponding elements of the 1058 * ranges are equal. 1059 */ 1060 template<typename _IIter1, typename _IIter2, typename _BinaryPredicate> 1061 inline bool 1062 equal(_IIter1 __first1, _IIter1 __last1, 1063 _IIter2 __first2, _BinaryPredicate __binary_pred) 1064 { 1065 // concept requirements 1066 __glibcxx_function_requires(_InputIteratorConcept<_IIter1>) 1067 __glibcxx_function_requires(_InputIteratorConcept<_IIter2>) 1068 __glibcxx_requires_valid_range(__first1, __last1); 1069 1070 for (; __first1 != __last1; ++__first1, ++__first2) 1071 if (!bool(__binary_pred(*__first1, *__first2))) 1072 return false; 1073 return true; 1074 } 1075 1076 /** 1077 * @brief Performs @b dictionary comparison on ranges. 1078 * @ingroup sorting_algorithms 1079 * @param first1 An input iterator. 1080 * @param last1 An input iterator. 1081 * @param first2 An input iterator. 1082 * @param last2 An input iterator. 1083 * @return A boolean true or false. 1084 * 1085 * <em>Returns true if the sequence of elements defined by the range 1086 * [first1,last1) is lexicographically less than the sequence of elements 1087 * defined by the range [first2,last2). Returns false otherwise.</em> 1088 * (Quoted from [25.3.8]/1.) If the iterators are all character pointers, 1089 * then this is an inline call to @c memcmp. 1090 */ 1091 template<typename _II1, typename _II2> 1092 inline bool 1093 lexicographical_compare(_II1 __first1, _II1 __last1, 1094 _II2 __first2, _II2 __last2) 1095 { 1096 // concept requirements 1097 typedef typename iterator_traits<_II1>::value_type _ValueType1; 1098 typedef typename iterator_traits<_II2>::value_type _ValueType2; 1099 __glibcxx_function_requires(_InputIteratorConcept<_II1>) 1100 __glibcxx_function_requires(_InputIteratorConcept<_II2>) 1101 __glibcxx_function_requires(_LessThanOpConcept<_ValueType1, _ValueType2>) 1102 __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>) 1103 __glibcxx_requires_valid_range(__first1, __last1); 1104 __glibcxx_requires_valid_range(__first2, __last2); 1105 1106 return std::__lexicographical_compare_aux(std::__niter_base(__first1), 1107 std::__niter_base(__last1), 1108 std::__niter_base(__first2), 1109 std::__niter_base(__last2)); 1110 } 1111 1112 /** 1113 * @brief Performs @b dictionary comparison on ranges. 1114 * @ingroup sorting_algorithms 1115 * @param first1 An input iterator. 1116 * @param last1 An input iterator. 1117 * @param first2 An input iterator. 1118 * @param last2 An input iterator. 1119 * @param comp A @link comparison_functors comparison functor@endlink. 1120 * @return A boolean true or false. 1121 * 1122 * The same as the four-parameter @c lexicographical_compare, but uses the 1123 * comp parameter instead of @c <. 1124 */ 1125 template<typename _II1, typename _II2, typename _Compare> 1126 bool 1127 lexicographical_compare(_II1 __first1, _II1 __last1, 1128 _II2 __first2, _II2 __last2, _Compare __comp) 1129 { 1130 typedef typename iterator_traits<_II1>::iterator_category _Category1; 1131 typedef typename iterator_traits<_II2>::iterator_category _Category2; 1132 typedef std::__lc_rai<_Category1, _Category2> __rai_type; 1133 1134 // concept requirements 1135 __glibcxx_function_requires(_InputIteratorConcept<_II1>) 1136 __glibcxx_function_requires(_InputIteratorConcept<_II2>) 1137 __glibcxx_requires_valid_range(__first1, __last1); 1138 __glibcxx_requires_valid_range(__first2, __last2); 1139 1140 __last1 = __rai_type::__newlast1(__first1, __last1, __first2, __last2); 1141 for (; __first1 != __last1 && __rai_type::__cnd2(__first2, __last2); 1142 ++__first1, ++__first2) 1143 { 1144 if (__comp(*__first1, *__first2)) 1145 return true; 1146 if (__comp(*__first2, *__first1)) 1147 return false; 1148 } 1149 return __first1 == __last1 && __first2 != __last2; 1150 } 1151 1152 /** 1153 * @brief Finds the places in ranges which don't match. 1154 * @ingroup non_mutating_algorithms 1155 * @param first1 An input iterator. 1156 * @param last1 An input iterator. 1157 * @param first2 An input iterator. 1158 * @return A pair of iterators pointing to the first mismatch. 1159 * 1160 * This compares the elements of two ranges using @c == and returns a pair 1161 * of iterators. The first iterator points into the first range, the 1162 * second iterator points into the second range, and the elements pointed 1163 * to by the iterators are not equal. 1164 */ 1165 template<typename _InputIterator1, typename _InputIterator2> 1166 pair<_InputIterator1, _InputIterator2> 1167 mismatch(_InputIterator1 __first1, _InputIterator1 __last1, 1168 _InputIterator2 __first2) 1169 { 1170 // concept requirements 1171 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) 1172 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) 1173 __glibcxx_function_requires(_EqualOpConcept< 1174 typename iterator_traits<_InputIterator1>::value_type, 1175 typename iterator_traits<_InputIterator2>::value_type>) 1176 __glibcxx_requires_valid_range(__first1, __last1); 1177 1178 while (__first1 != __last1 && *__first1 == *__first2) 1179 { 1180 ++__first1; 1181 ++__first2; 1182 } 1183 return pair<_InputIterator1, _InputIterator2>(__first1, __first2); 1184 } 1185 1186 /** 1187 * @brief Finds the places in ranges which don't match. 1188 * @ingroup non_mutating_algorithms 1189 * @param first1 An input iterator. 1190 * @param last1 An input iterator. 1191 * @param first2 An input iterator. 1192 * @param binary_pred A binary predicate @link functors 1193 * functor@endlink. 1194 * @return A pair of iterators pointing to the first mismatch. 1195 * 1196 * This compares the elements of two ranges using the binary_pred 1197 * parameter, and returns a pair 1198 * of iterators. The first iterator points into the first range, the 1199 * second iterator points into the second range, and the elements pointed 1200 * to by the iterators are not equal. 1201 */ 1202 template<typename _InputIterator1, typename _InputIterator2, 1203 typename _BinaryPredicate> 1204 pair<_InputIterator1, _InputIterator2> 1205 mismatch(_InputIterator1 __first1, _InputIterator1 __last1, 1206 _InputIterator2 __first2, _BinaryPredicate __binary_pred) 1207 { 1208 // concept requirements 1209 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>) 1210 __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>) 1211 __glibcxx_requires_valid_range(__first1, __last1); 1212 1213 while (__first1 != __last1 && bool(__binary_pred(*__first1, *__first2))) 1214 { 1215 ++__first1; 1216 ++__first2; 1217 } 1218 return pair<_InputIterator1, _InputIterator2>(__first1, __first2); 1219 } 1220 1221 _GLIBCXX_END_NESTED_NAMESPACE 1222 1223 // NB: This file is included within many other C++ includes, as a way 1224 // of getting the base algorithms. So, make sure that parallel bits 1225 // come in too if requested. 1226 #ifdef _GLIBCXX_PARALLEL 1227 # include <parallel/algobase.h> 1228 #endif 1229 1230 #endif 1231