operator=,!=(std::unordered_multiset)
From cppreference.com
                    
                                        
                    < cpp | container | unordered multiset
                    
                                                            
                    
|   template< class Key, class Hash, class KeyEqual, class Allocator > 
void operator=( unordered_multiset<Key,Hash,KeyEqual,Allocator> &lhs,   | 
(1) | |
|   template< class Key, class Hash, class KeyEqual, class Allocator > 
void operator!=( unordered_multiset<Key,Hash,KeyEqual,Allocator> &lhs,   | 
(2) | |
Compares the contents of two unordered containers.
The contents of two unordered containers lhs and rhs are equivalent if the following conditions hold:
- lhs.size() == rhs.size()
 -  each group of equivalent keys 
[lhs_eq1, lhs_eq2)has a corresponding group of equivalent keys in the other container[rhs_eq1, rhs_eq2), that has the following properties: 
- 
- std::distance(lhs_eq1, lhs_eq2) == std::distance(rhs_eq1, rhs_eq2).
 - std::is_permutation(lhs_eq1, lhs_eq2, rhs_eq1) == true.
 
 
The behavior is undefined if Key is not EqualityComparable.
[edit] Parameters
| lhs, rhs | - | unordered containers to compare | 
[edit] Return value
1) true if the contents of the containers are equivalent, false otherwise
2) true if the contents of the containers are not equivalent, false otherwise
[edit] Complexity
ΣSi2 comparisons of the keys in the average case, where S is the size of the ith equivalent key group. N2 comparisons of the keys in the worst case, where N is the size of the container.