C++ Programming Code Examples
C++ > Data Structures and Algorithm Analysis in C++ Code Examples
Queue implemented with STL list
/* Queue implemented with STL list */
#include <iostream>
#include <list>
#include "dsexceptions.h"
using namespace std;
template <class Object>
class Queue
{
public:
bool isEmpty( ) const;
const Object & getFront( ) const;
void makeEmpty( );
Object dequeue( );
void enqueue( const Object & x );
private:
list<Object> theList;
};
template <class Object>
bool Queue<Object>::isEmpty( ) const
{
return theList.empty( );
}
template <class Object>
const Object & Queue<Object>::getFront( ) const
{
if( isEmpty( ) )
throw Underflow( );
return theList.front( );
}
template <class Object>
void Queue<Object>::makeEmpty( )
{
while( !isEmpty( ) )
dequeue( );
}
template <class Object>
Object Queue<Object>::dequeue( )
{
Object frontItem = getFront( );
theList.pop_front( );
return frontItem;
}
template <class Object>
void Queue<Object>::enqueue( const Object & x )
{
theList.push_back( x );
}
int main( )
{
Queue<int> q;
for( int j = 0; j < 5; j++ )
{
for( int i = 0; i < 5; i++ )
q.enqueue( i );
while( !q.isEmpty( ) )
cout << q.dequeue( ) << endl;
}
return 0;
}
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