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queue::queue
member functions:
queue::back
queue::empty
queue::front
queue::pop
queue::push
queue::size


queue::size

public member function
size_type size ( ) const;

Return size

Returns the number of elements in the queue.

This member function effectively calls the member with the same name in the underlying container object.

Parameters

none

Return Value

The number of elements that conform the queue's container content.

Member type size_type is an unsigned integral type.

Example

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// queue::size
#include <iostream>
#include <queue>
using namespace std;
int main ()
{
  queue<int> myints;
  cout << "0. size: " << (int) myints.size() << endl;
  for (int i=0; i<5; i++) myints.push(i);
  cout << "1. size: " << (int) myints.size() << endl;
  myints.pop();
  cout << "2. size: " << (int) myints.size() << endl;
  return 0;
}


Output:
0. size: 0
1. size: 5
2. size: 4

Complexity

Constant.

See also

queue::empty Test whether container is empty (public member function)