public member function
<queue>

std::queue::size

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)