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std::flat_map::erase(3)        C++ Standard Libary	 std::flat_map::erase(3)

NAME
     std::flat_map::erase - std::flat_map::erase

Synopsis
	iterator  erase( iterator position );			      (1) (since
     C++23)
	iterator erase( const_iterator pos );			     (2)  (since
     C++23)
	iterator  erase( const_iterator first, const_iterator last ); (3) (since
     C++23)
	size_type erase( const Key& key );			     (4)  (since
     C++23)
	template<  class K >					      (5) (since
     C++23)
	size_type erase( K&& x );

	Removes specified elements from the container.

	1,2) Removes the element at pos.
	3) Removes the elements in the range [first,  last),  which  must  be  a
     valid range in
	*this.
	4) Removes the element (if one exists) with the key equivalent to key.
	5)  Removes  all elements with key that compares equivalent to the value
     x. This
	overload participates in overload resolution only if the qualified-id
	Compare::is_transparent is valid and denotes a type, and neither  itera-
     tor nor
	const_iterator	is implicitly convertible from K. It allows calling this
     function
	without constructing an instance of Key.

	 Information on iterator invalidation is copied from here

	The iterator pos must be valid and dereferenceable. Thus the end() iter-
     ator (which
	is valid, but is not dereferenceable) cannot be used as a value for pos.

Parameters
	pos	    - iterator to the element to remove
	first, last - range of elements to remove
	key	    - key value of the elements to remove
	x	    - a value of any type that	can  be  transparently	compared
     with a key
		      denoting the elements to remove

Return value
	1-3) Iterator following the last removed element.
	4) Number of elements removed (0 or 1).
	5) Number of elements removed.

Exceptions
	1-3) Throws nothing.
	4,5) Any exceptions thrown by the Compare object.

Complexity
	Depends on underlying containers. Typically linear.

	 This section is incomplete
	 Reason: revision required

Example
     // Run this code

      #include <flat_map>
      #include <iostream>

      int main()
      {
	  std::flat_map<int, std::string> c =
	  {
	      {1, "one"}, {2, "two"}, {3, "three"},
	      {4, "four"}, {5, "five"}, {6, "six"}
	  };

	  // erase all odd numbers from c
	  for (auto it = c.begin(); it != c.end();)
	  {
	      if (it->first % 2 != 0)
		  it = c.erase(it);
	      else
		  ++it;
	  }

	  for (auto& p : c)
	      std::cout << p.second << ' ';
	  std::cout << '\n';
      }

Output:
      two four six

See also
	clear clears the contents
	      (public member function)

Category:
	  * Todo with reason

http://cppreference.com 	   2024.06.10		 std::flat_map::erase(3)
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