1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 // <deque> 10 11 // iterator erase(const_iterator f) 12 13 // Erasing items from the beginning or the end of a deque shall not invalidate iterators 14 // to items that were not erased. 15 16 #include <deque> 17 #include <cassert> 18 19 #include "test_macros.h" 20 21 template <typename C> del_at_start(C c)22void del_at_start(C c) 23 { 24 typename C::iterator first = c.begin(); 25 typename C::iterator it1 = first + 1; 26 typename C::iterator it2 = c.end() - 1; 27 28 c.erase (first); 29 30 typename C::iterator it3 = c.begin(); 31 typename C::iterator it4 = c.end() - 1; 32 assert( it1 == it3); 33 assert( *it1 == *it3); 34 assert(&*it1 == &*it3); 35 assert( it2 == it4); 36 assert( *it2 == *it4); 37 assert(&*it2 == &*it4); 38 } 39 40 template <typename C> del_at_end(C c)41void del_at_end(C c) 42 { 43 typename C::iterator first = c.end() - 1; 44 typename C::iterator it1 = c.begin(); 45 typename C::iterator it2 = first - 1; 46 47 c.erase (first); 48 49 typename C::iterator it3 = c.begin(); 50 typename C::iterator it4 = c.end() - 1; 51 assert( it1 == it3); 52 assert( *it1 == *it3); 53 assert(&*it1 == &*it3); 54 assert( it2 == it4); 55 assert( *it2 == *it4); 56 assert(&*it2 == &*it4); 57 } 58 main(int,char **)59int main(int, char**) 60 { 61 std::deque<int> queue; 62 for (int i = 0; i < 20; ++i) 63 queue.push_back(i); 64 65 while (queue.size() > 1) 66 { 67 del_at_start(queue); 68 del_at_end(queue); 69 queue.pop_back(); 70 } 71 72 return 0; 73 } 74