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

NAME
     std::flat_map::empty - std::flat_map::empty

Synopsis
	[[nodiscard]] bool empty() const noexcept;  (since C++23)

	Checks	if the underlying containers have no elements. Equivalent to re-
     turn begin()
	== end();.

Parameters
	(none)

Return value
	true if the underlying containers are empty, false otherwise.

Complexity
	Constant.

Example
	The following code uses empty to check if a std::flat_map<int, int> con-
     tains any
	elements:

     // Run this code

      #include <iostream>
      #include <flat_map>
      #include <utility>

      int main()
      {
	  std::flat_map<int,int> numbers;
	  std::cout << std::boolalpha;
	  std::cout << "Initially,  numbers.empty():  "  <<  numbers.empty()  <<
     '\n';

	  numbers.emplace(42, 13);
	  numbers.insert(std::make_pair(13317, 123));
	  std::cout  <<  "After  adding  elements,  numbers.empty():  "  << num-
     bers.empty() << '\n';
      }

Output:
      Initially, numbers.empty(): true
      After adding elements, numbers.empty(): false

See also
	size	returns the number of elements
		(public member function)
	empty	checks whether the container is empty
	(C++17) (function template)

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