std::unordered_multimap::find
From cppreference.com
< cpp | container | unordered multimap
iterator find( const Key& key ); |
(1) | |
const_iterator find( const Key& key ) const; |
(2) | |
template< class K > iterator find( const K& x ); |
(3) | (since C++20) |
template< class K > const_iterator find( const K& x ) const; |
(4) | (since C++20) |
1,2) Finds an element with key equivalent to
key
. 3,4) Finds an element with key that compares equivalent to the value
x
. This overload only participates in overload resolution if the qualified-id Hash::transparent_key_equal is valid and denotes a type. This assumes that such Hash is callable with both K and Key type, and that its key_equal 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
Iterator to an element with key equivalent to key
. 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.
Example
Run this code
#include <iostream> #include <unordered_map> int main() { // simple comparison demo std::unordered_multimap<int,char> example = {{1,'a'},{2,'b'}}; auto search = example.find(2); if (search != example.end()) { std::cout << "Found " << search->first << " " << search->second << '\n'; } else { std::cout << "Not found\n"; } }
Output:
Found 2 b
See also
returns the number of elements matching specific key (public member function) | |
returns range of elements matching a specific key (public member function) |