std::unordered_set::unordered_set

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explicit unordered_set( size_type bucket_count = /*implementation-defined*/,

                        const Hash& hash = Hash(),
                        const KeyEqual& equal = KeyEqual(),

                        const Allocator& alloc = Allocator() );
(1) (since C++11)
explicit unordered_set( const Allocator& alloc );
(1) (since C++11)
template< class InputIt >

unordered_set( InputIt first, InputIt last,
               size_type bucket_count = /*implementation-defined*/,
               const Hash& hash = Hash(),
               const KeyEqual& equal = KeyEqual(),

               const Allocator& alloc = Allocator() );
(2) (since C++11)
unordered_set( const unordered_set& other );
(3) (since C++11)
unordered_set( const unordered_set& other, const Allocator& alloc );
(3) (since C++11)
unordered_set( unordered_set&& other );
(4) (since C++11)
unordered_set( unordered_set&& other, const Allocator& alloc );
(4) (since C++11)
unordered_set( std::initializer_list<value_type> init,

               size_type bucket_count = /*implementation-defined*/,
               const Hash& hash = Hash(),
               const KeyEqual& equal = KeyEqual(),

               const Allocator& alloc = Allocator() );
(5) (since C++11)

Constructs new container from a variety of data sources. Optionally uses user supplied bucket_count as a minimal number of buckets to create, hash as the hash function, equal as the function to compare keys and alloc as the allocator.

1) default constructor. Constructs empty container.

2) constructs the container with the contents of the range [first, last).

3) copy constructor. Constructs the container with the copy of the contents of other. If alloc is not provided, allocator is obtained by calling std::allocator_traits<allocator_type>::select_on_copy_construction(other).

4) move constructor. Constructs the container with the contents of other using move semantics. If alloc is not provided, allocator is obtained by move-construction from the allocator belonging to other.

5) constructs the container with the contents of the initializer list init.

Contents

[edit] Parameters

alloc - allocator to use for all memory allocations of this container
bucket_count - minimal number of buckets to use on initialization. If it is not specified, implementation-defined default value is used
hash - hash function to use
equal - comparison function to use for all key comparisons of this container
first, last - the range to copy the elements from
other - another container to be used as source to initialize the elements of the container with
init - initializer list to initialize the elements of the container with
Type requirements
-
InputIt must meet the requirements of InputIterator.

[edit] Complexity

1) constant

2) linear in distance between first and last

3) linear in size of other

4) constant. If alloc is given and alloc != other.get_allocator(), then linear.

5) linear in size of init

[edit] Example

[edit] See also

assigns values to the container
(public member function)