queue Functions

Illustrates how to use the queue::push, queue::pop, queue::empty, queue::back, queue::front, and queue::size Standard Template Library (STL) functions in Visual C++.

queue::push( ); 
queue::pop( ); 
queue::empty( ); 
queue::back( ); 
queue::front( ); 
queue::size( );

Description

Note

The class/parameter names in the prototype do not match the version in the header file. Some have been modified to improve readability.

The sample shows the queue implementation using list and deque containers.

Example

// queue.cpp
// compile with: /EHsc
//
// Functions:
//    queue::push(), queue::pop(), queue::empty(), queue::back(),
//    queue::front(),queue::size()

#include <list>
#include <iostream>
#include <queue>
#include <deque>

using namespace std ;

// Using queue with list
typedef list<int > INTLIST;
typedef queue<int>  INTQUEUE;

// Using queue with deque
typedef deque<char*> CHARDEQUE;
typedef queue<char*> CHARQUEUE;

int main(void)
{
    size_t size_q;
    INTQUEUE q;
    CHARQUEUE p;

    // Insert items in the queue(uses list)
    q.push(42);
    q.push(100);
    q.push(49);
    q.push(201);

    // Output the size of queue
    size_q = q.size();
    cout << "size of q is:" << size_q << endl;

    // Output items in queue using front()
    // and use pop() to get to next item until
    // queue is empty
    while (!q.empty())
    {
        cout << q.front() << endl;
        q.pop();
    }

// Insert items in the queue(uses deque)
    p.push("cat");
    p.push("ape");
    p.push("dog");
    p.push("mouse");
    p.push("horse");

    // Output the item inserted last using back()
    cout << p.back() << endl;

    // Output the size of queue
    size_q = p.size();
    cout << "size of p is:" << size_q << endl;

    // Output items in queue using front()
    // and use pop() to get to next item until
    // queue is empty
    while (!p.empty())
    {
        cout << p.front() << endl;
        p.pop();
    }
}

Output

size of q is:4
42
100
49
201
horse
size of p is:5
cat
ape
dog
mouse
horse

Requirements

Header: <queue>

See Also

Concepts

Standard Template Library Samples