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

NAME
       std::set::empty - std::set::empty

Synopsis
	  bool empty() const;			      (until C++11)
	  bool empty() const noexcept;		      (since C++11)
						      (until C++20)
	  [[nodiscard]]	bool empty() const noexcept;  (since C++20)

	  Checks  if  the  container  has no elements, i.e. whether begin() ==
       end().

Parameters
	  (none)

Return value
	  true if the container	is empty, false	otherwise

Complexity
	  Constant.

Example
	  The following	code uses empty	to check if a  std::set<int>  contains
       any elements:

       // Run this code

	#include <set>
	#include <iostream>

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

	    numbers.insert(42);
	    numbers.insert(13317);
	    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		  2022.07.31		    std::set::empty(3)

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