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

NAME
       std::flat_set::empty - std::flat_set::empty

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

	  Checks  if  the  underlying container	has no elements. Equivalent to
       return begin() ==
	  end();.

Parameters
	  (none)

Return value
	  true if the underlying container is empty, false otherwise.

Complexity
	  Constant.

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

       // Run this code

	#include <iostream>
	#include <flat_set>

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

	    numbers.insert(42);
	    numbers.insert(19937);
	    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_set::empty(3)

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