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std::unorde...ltimap::find(3) C++ Standard Libarystd::unorde...ltimap::find(3)

NAME
       std::unordered_multimap::find - std::unordered_multimap::find

Synopsis
	  iterator find( const Key& key	);	       (1) (since C++11)
	  const_iterator find( const Key& key )	const; (2) (since C++11)
	  template< class K >			       (3) (since C++20)
	  iterator find( const K& x );
	  template< class K >			       (4) (since C++20)
	  const_iterator find( const K&	x ) const;

	  1,2)	Finds an element with key equivalent to	key. If	there are sev-
       eral elements with
	  the requested	key in the container, any of them may be returned.
	  3,4) Finds an	element	with key that compares equivalent to the value
       x. This
	  overload participates	in overload resolution only if Hash::is_trans-
       parent and
	  KeyEqual::is_transparent are valid and each denotes a	type. This as-
       sumes that such
	  Hash is callable with	both K and Key type, and that the KeyEqual  is
       transparent,
	  which,  together,  allows calling this function without constructing
       an instance of
	  Key.

Parameters
	  key -	key value of the element to search for
	  x   -	a value	of any type that can be	transparently compared with  a
       key

Return value
	  An  iterator	to the requested element. If no	such element is	found,
       past-the-end (see
	  end()) iterator is returned.

Complexity
	  Constant on average, worst case linear in the	size of	the container.

Notes
		  Feature-test macro	      Value    Std		  Fea-
       ture
							     Heterogeneous
       comparison lookup
	  __cpp_lib_generic_unordered_lookup 201811L (C++20) in	unordered  as-
       sociative
							     containers; over-
       loads (3,4)

Example
       // Run this code

	#include <iostream>
	#include <unordered_map>

	int main()
	{
	    // Simple comparison demo.
	    std::unordered_multimap<int,char> example =	{{1,'a'}, {2,'b'}};

	    if (auto search = example.find(2); search != example.end())
		std::cout  << "Found " << search->first	<< ' ' << search->sec-
       ond << '\n';
	    else
		std::cout << "Not found\n";
	}

Output:
	Found 2	b

See also
	  count	      returns the number of elements matching specific key
		      (public member function)
	  equal_range returns range of elements	matching a specific key
		      (public member function)

http://cppreference.com		  2024.06.10	 std::unorde...ltimap::find(3)

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