std::unordered_map::at

 

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std::unordered_map

成员函数 Original: Member functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

unordered_map::unordered_map

unordered_map::~unordered_map

unordered_map::operator=

unordered_map::get_allocator

迭代器 Original: Iterators The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

unordered_map::begin unordered_map::cbegin

unordered_map::end unordered_map::cend

容量 Original: Capacity The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

unordered_map::erase

unordered_map::size

unordered_map::max_size

修饰符 Original: Modifiers The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

unordered_map::clear

unordered_map::insert

unordered_map::emplace

unordered_map::emplace_hint

unordered_map::erase

unordered_map::swap

查找 Original: Lookup The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

unordered_map::count

unordered_map::find

unordered_map::equal_range

斗接口 Original: Bucket interface The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

unordered_map::begin2

unordered_map::end2

unordered_map::bucket_count

unordered_map::max_bucket_count

unordered_map::bucket_size

unordered_map::bucket

哈希政策 Original: Hash policy The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

unordered_map::load_factor

unordered_map::max_load_factor

unordered_map::rehash

unordered_map::reserve

观察员 Original: Observers The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

unordered_map::hash_function

unordered_map::key_eq

 

T& at( const Key& key );	(1)	（C++11 起）
const T & at( const Key& key ) const;	(2)	（C++11 起）

关键相当于key的元素，返回一个引用的映射值。如果不存在这样的元素，被抛出的异常类型std::out_of_range.

Original:

Returns a reference to the mapped value of the element with key equivalent to key. If no such element exists, an exception of type std::out_of_range is thrown.

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参数

key

-

找到的元素的键 Original: the key of the element to find The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

返回值

所请求的元素的映射值的参考

Original:

Reference to the mapped value of the requested element

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例外

std::out_of_range如果容器不具有与指定key的元素

Original:

std::out_of_range if the container does not have an element with the specified key

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复杂性

Average case: constant, worst case: linear in size.

另请参阅

operator[]	访问指定的元素 Original: access specified element The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （公共成员函数）