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std::priority_queue::top(3)   C++ Standard Libary  std::priority_queue::top(3)

NAME
       std::priority_queue::top	- std::priority_queue::top

Synopsis
	  const_reference top()	const;

	  Returns reference to the top element in the priority queue. This el-
       ement will be
	  removed  on a	call to	pop(). If default comparison function is used,
       the returned
	  element is also the greatest among the elements in the queue.

Parameters
	  (none)

Return value
	  Reference to the top element as if obtained by a call	to c.front()

Complexity
	  Constant.

Example
       // Run this code

	#include <queue>
	#include <iostream>

	struct Event
	{
	    int	priority{};
	    char data{'	'};

	    friend bool	operator< (Event const&	lhs, Event const& rhs) {
		return lhs.priority < rhs.priority;
	    }

	    friend std::ostream& operator<< (std::ostream& os, Event const& e)
       {
		return os << "{	" << e.priority	<< ", '" << e.data << "' } ";
	    }
	};

	int main()
	{
	    std::priority_queue<Event> events;

	    std::cout << "Fill the events queue:\n";

	    for	(auto const e:	{  Event{6,'L'},  {8,'I'},  {9,'S'},  {1,'T'},
       {5,'E'},	{3,'N'}	}) {
		std::cout << e << ' ';
		events.push(e);
	    }

	    std::cout << "\n" "Process events:\n";

	    for	(; !events.empty(); events.pop()) {
		Event const& e = events.top();
		std::cout << e << ' ';
	    }
	}

Output:
	Fill the events	queue:
	{ 6, 'L' }  { 8, 'I' }	{ 9, 'S' }  { 1, 'T' }	{ 5, 'E' }  { 3, 'N' }
	Process	events:
	{ 9, 'S' }  { 8, 'I' }	{ 6, 'L' }  { 5, 'E' }	{ 3, 'N' }  { 1, 'T' }

See also
	  pop removes the top element
	      (public member function)

http://cppreference.com		  2022.07.31	   std::priority_queue::top(3)

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