1 //===----------------------------------------------------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 // <deque> 11 12 // iterator erase(const_iterator f) 13 14 // Erasing items from the beginning or the end of a deque shall not invalidate iterators 15 // to items that were not erased. 16 17 #include <deque> 18 #include <cassert> 19 20 template <typename C> 21 void del_at_start(C c) 22 { 23 typename C::iterator first = c.begin(); 24 typename C::iterator it1 = first + 1; 25 typename C::iterator it2 = c.end() - 1; 26 27 c.erase (first); 28 29 typename C::iterator it3 = c.begin(); 30 typename C::iterator it4 = c.end() - 1; 31 assert( it1 == it3); 32 assert( *it1 == *it3); 33 assert(&*it1 == &*it3); 34 assert( it2 == it4); 35 assert( *it2 == *it4); 36 assert(&*it2 == &*it4); 37 } 38 39 template <typename C> 40 void del_at_end(C c) 41 { 42 typename C::iterator first = c.end() - 1; 43 typename C::iterator it1 = c.begin(); 44 typename C::iterator it2 = first - 1; 45 46 c.erase (first); 47 48 typename C::iterator it3 = c.begin(); 49 typename C::iterator it4 = c.end() - 1; 50 assert( it1 == it3); 51 assert( *it1 == *it3); 52 assert(&*it1 == &*it3); 53 assert( it2 == it4); 54 assert( *it2 == *it4); 55 assert(&*it2 == &*it4); 56 } 57 58 int main() 59 { 60 std::deque<int> queue; 61 for (int i = 0; i < 20; ++i) 62 queue.push_back(i); 63 64 while (queue.size() > 1) 65 { 66 del_at_start(queue); 67 del_at_end(queue); 68 queue.pop_back(); 69 } 70 } 71
