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

NAME
     std::flat_map::clear - std::flat_map::clear

Synopsis
	void clear() noexcept;	(since C++23)

	Erases	all elements from the container adaptor. After this call, size()
     returns
	zero.

	Invalidates any references, pointers, and iterators  referring	to  con-
     tained elements.

Parameters
	(none)

Return value
	(none)

Complexity
	Linear	in  the  size of the container adaptor, i.e., the number of ele-
     ments.

Example
     // Run this code

      #include <iostream>
      #include <string_view>
      #include <flat_map>

      void print_info(std::string_view rem, const std::flat_map<int, char>& v)
      {
	  std::cout << rem << "{ ";
	  for (const auto& [key, value] : v)
	      std::cout << '[' << key << "]:" << value << ' ';
	  std::cout << "}\n";
	  std::cout << "Size=" << v.size() << '\n';
      }

      int main()
      {
	  std::flat_map<int, char> container{{1, 'x'}, {2, 'y'}, {3, 'z'}};
	  print_info("Before clear: ", container);
	  container.clear();
	  print_info("After clear: ", container);
      }

Output:
      Before clear: { [1]:x [2]:y [3]:z }
      Size=3
      After clear: { }
      Size=0

See also
	erase erases elements
	      (public member function)

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