std::unordered_multiset<Key,Hash,KeyEqual,Allocator>::find

iterator find( const Key& key );

iterator find( const Key& key, size_t hash );

const_iterator find( const Key& key ) const;

const_iterator find( const Key& key, size_t hash ) const;

template< class K > iterator find( const K& x );

template< class K > iterator find( const K& x, size_t hash );

template< class K > const_iterator find( const K& x ) const;

template< class K > const_iterator find( const K& x, size_t hash ) const;

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.

#include <iostream>
#include <unordered_set>
 
int main()
{  
// simple comparison demo
    std::unordered_multiset<int> example = {1, 2, 3, 4};
 
    auto search = example.find(2);
    if (search != example.end()) {
        std::cout << "Found " << (*search) << '\n';
    } else {
        std::cout << "Not found\n";
    }
 
 
}

Found 2