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vector::push_back and vector::pop_back

Illustrates how to use the vector::push_back and vector::pop_back Standard Template Library (STL) functions in Visual C++.

template<class _TYPE, class _A> 
   void vector::push_back( 
      const _TYPE& X 
   ); 
template<class _TYPE, class _A> 
   void vector::pop_back();

Remarks

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 declares an empty vector of integers. It adds three integers to the vector, and then deletes one. Finally, it generates the remaining elements in the vector.

Example

// Pushpop.cpp
// compile with: /EHsc
// Illustrates how to use the push and pop member
// functions of the vector container.
//
// Functions:
//
// vector::push_back - Appends (inserts) an element to the end of a
// vector, allocating memory for it if necessary.
//
// vector::pop_back -  Erases the last element of the vector.
//
// vector::begin - Returns an iterator to start traversal of the vector.
//
// vector::end - Returns an iterator for the last element of the vector.
//
// vector::iterator - Traverses the vector.
//
//////////////////////////////////////////////////////////////////////

// The debugger can't handle symbols more than 255 characters long.
// STL often creates symbols longer than that.
// When symbols are longer than 255 characters, the warning is disabled.
#pragma warning(disable:4786)

#include <iostream>
#include <vector>

using namespace std ;

typedef vector<int> INTVECTOR;

int main()
{
    // Dynamically allocated vector begins with 0 elements.
    INTVECTOR theVector;

    // Iterator is used to loop through the vector.
    INTVECTOR::iterator theIterator;

    // Add one element to the end of the vector, an int with the value 42.
    // Allocate memory if necessary.
    theVector.push_back(42) ;

    // Add two more elements to the end of the vector.
    // theVector will contain [ 42, 1, 109 ].
    theVector.push_back(1) ;
    theVector.push_back(109) ;

    // Erase last element in vector.
    theVector.pop_back();

    // Print contents of theVector. Shows [ 42, 1 ]
    cout << "theVector [ " ;
    for (theIterator = theVector.begin(); theIterator != theVector.end();
         theIterator+)
    {
        cout << *theIterator;
        if (theIterator != theVector.end()-1) cout << ", ";
                                             
    }
    cout << " ]" << endl ;
}

theVector [ 42, 1 ]

Requirements

Header: <vector>

See Also

Concepts

Standard Template Library Samples

Reference

abs (<valarray>)