C++ Queue Library - push() Function

Description

The C++ function std::priority_queue::push() inserts new element in sorted order in the priority_queue by performing

move operation. This member function increases size of queue by one.

Declaration

Following is the declaration for std::priority_queue::push() function form std::queue header.

C++11

void push (value_type&& val);

Parameters

val − Value to be assigned to newly inserted element.

Return value

None.

Exceptions

This member function never throws exception.

Example

The following example shows the usage of std::priority_queue::push() function.

#include <iostream>
#include <queue>

using namespace std;

int main(void) {
   auto it1 = {3, 1, 5, 2, 4};
   priority_queue<int> q1(less<int>(), it1);
   priority_queue<int> q2;

   for (int i = 0; i < 5; ++i) {
      q2.push(move(q1.top()));
      q1.pop();
   }

   cout << "Contents of q1" << endl;
   while (!q1.empty()) {
      cout << q1.top() << endl;
      q1.pop();
   }

   cout << "Contents of q2" << endl;
   while (!q2.empty()) {
      cout << q2.top() << endl;
      q2.pop();
   }

   return 0;
}

Let us compile and run the above program, this will produce the following result −

Contents of q1
Contents of q2
5
4
3
2
1