std::multiset<Key,Compare,Allocator>::merge
 template<class C2> void merge(std::set<Key, C2, Allocator>& source);  |  (1) | (since C++17) | 
 template<class C2> void merge(std::set<Key, C2, Allocator>&& source);  |  (2) | (since C++17) | 
 template<class C2> void merge(std::multiset<Key, C2, Allocator>& source);  |  (3) | (since C++17) | 
 template<class C2> void merge(std::multiset<Key, C2, Allocator>&& source);  |  (4) | (since C++17) | 
Attempts to extract ("splice") each element in source and insert it into *this using the comparison object of *this.
No elements are copied or moved, only the internal pointers of the container nodes are repointed. All pointers and references to the transferred elements remain valid, but now refer into *this, not into source.
The behavior is undefined if get_allocator() != source.get_allocator().
Parameters
| source | - | compatible container to transfer the nodes from | 
Return value
(none).
Exceptions
Does not throw unless comparison throws.
Complexity
N*log(size()+N)), where N is source.size().
Example
See also
|  
 (C++17)   |   extracts nodes from the container  (public member function)  | 
|  inserts elements or nodes (since C++17)  (public member function)  | 
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