std::multimap::insert

Parameters

val

Value to be copied to (or moved as) the inserted element.
Member type value_type is the type of the elements in the container, defined in multimap as pair<const key_type,mapped_type> (see multimap member types).

The template parameter P shall be a type convertible to value_type.

The signatures taking an argument of type P&& are only called if std::is_constructible<value_type,P&&> is true.

If P is instantiated as a reference type, the argument is copied.

position

Hint for the position where the element can be inserted.

The function optimizes its insertion time if position points to the element that will precede the inserted element.

The function optimizes its insertion time if position points to the element that will follow the inserted element (or to the end, if it would be the last).

Notice that this is just a hint and does not force the new element to be inserted at that position within the multimap container (the elements in a multimap always follow a specific order depending on their key).
Member types iterator and const_iterator are defined in multimap as bidirectional iterator types that point to elements.

first, last

Iterators specifying a range of elements. Copies of the elements in the range [first,last) are inserted in the container.
Notice that the range includes all the elements between first and last, including the element pointed by first but not the one pointed by last.
The function template argument InputIterator shall be an input iterator type that points to elements of a type from which value_type objects can be constructed.

il

An initializer_list object. Copies of these elements are inserted.
These objects are automatically constructed from initializer list declarators.
Member type value_type is the type of the elements contained in the container, defined in multimap as pair<const key_type,mapped_type> (see multimap member types).

Return value

Example

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// multimap::insert (C++98)
#include <iostream>
#include <map>
int main ()
{
  std::multimap<char,int> mymultimap;
  std::multimap<char,int>::iterator it;
  // first insert function version (single parameter):
  mymultimap.insert ( std::pair<char,int>('a',100) );
  mymultimap.insert ( std::pair<char,int>('z',150) );
  it=mymultimap.insert ( std::pair<char,int>('b',75) );
  // second insert function version (with hint position):
  mymultimap.insert (it, std::pair<char,int>('c',300));  // max efficiency inserting
  mymultimap.insert (it, std::pair<char,int>('z',400));  // no max efficiency inserting
  // third insert function version (range insertion):
  std::multimap<char,int> anothermultimap;
  anothermultimap.insert(mymultimap.begin(),mymultimap.find('c'));
  // showing contents:
  std::cout << "mymultimap contains:\n";
  for (it=mymultimap.begin(); it!=mymultimap.end(); ++it)
    std::cout << (*it).first << " => " << (*it).second << '\n';
  std::cout << "anothermultimap contains:\n";
  for (it=anothermultimap.begin(); it!=anothermultimap.end(); ++it)
    std::cout << (*it).first << " => " << (*it).second << '\n';
  return 0;
}

mymultimap contains:
a => 100
b => 75
c => 300
z => 400
z => 150
anothermultimap contains:
a => 100
b => 75

Complexity

Iterator validity

Data races

Exception safety

See also

multimap::find

Get iterator to element (public member function)

multimap::erase

Erase elements (public member function)