INFO: STL Sample for deque::push_front, deque::pop_front Functions

ID: Q156768

The information in this article applies to:

The Standard C++ Library, used with:
- Microsoft Visual C++, 32-bit Editions, versions 4.2, 5.0, 6.0

SUMMARY

The sample code below illustrates how to use the deque::push_front and deque::pop_front STL functions in Visual C++. Deque is a double-ended queue where elements can be inserted and removed from the front and from the back.

MORE INFORMATION

Required Header


   <deque>

Prototype


   void push_front(const T& x);
   void pop_front();

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

Description

The push_front function inserts an element with value x at the beginning of the deque container. The pop_front function removes the first element of the deque container, which must be non-empty.

Sample Code


   ////////////////////////////////////////////////////////////////////// 
   // 
   // Compile options needed: -GX
   // 
   // deque.cpp :
   // 
   // Functions:
   // 
   //    deque::push_front
   //    deque::pop_front
   // 
   // Written by Bobby Mattappally
   // of Microsoft Product Support Services,
   // Copyright (c) 1996 Microsoft Corporation. All rights reserved.
   ////////////////////////////////////////////////////////////////////// 

   /* Compile options needed:-GX
   */ 

   #include <iostream>
   #include <deque>

#if _MSC_VER > 1020   // if VC++ version is > 4.2
   using namespace std;  // std c++ libs implemented in std
   #endif

   typedef deque<int, allocator<int> >  INTDEQUE;
   void printcontents (INTDEQUE  deque);

   void main()
   {

       INTDEQUE  dequetest;

       dequetest.push_front(1);
       dequetest.push_front(2);
       dequetest.push_front(3);
       printcontents (dequetest);
       dequetest.pop_front();
       printcontents (dequetest);
       dequetest.pop_front();
       printcontents (dequetest);

   }

   //function to print the contents of deque
   void printcontents (INTDEQUE  deque)
   {
       INTDEQUE::iterator pdeque;

       cout <<"The output is:"<<endl;

           for(pdeque = deque.begin();
           pdeque != deque.end();
           pdeque++)
       {
           cout << *pdeque <<endl ;
       }

   }

Program output is:


   The output is:
   3
   2
   1
   The output is:
   2
   1
   The output is:
   1

REFERENCES

Visual C++ Books On Line: Visual C++ Books:C/C++:Standard C++ Library Reference.

Additional query words: STL STLSample push_front pop_front deque

Keywords : kbcode kbVC420 kbVC500 kbVC600 kbDSupport STLIss
Version : winnt:4.2,5.0,6.0
Platform : winnt
Issue type : kbinfo