C++ Programming Code Examples
C++ > Beginners Lab Assignments Code Examples
Implementing Queue as a Class
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/* Implementing Queue as a Class */
# include<iostream.h>
# include<conio.h>
# define SIZE 20
class queue
{
int a[SIZE];
int front;
int rear;
public:
queue();
~queue();
void insert(int i);
int remove();
int isempty();
int isfull();
};
queue::queue()
{
front=0;
rear=0;
}
queue::~queue()
{
delete []a;
}
void queue::insert(int i)
{
if(isfull())
{
cout<<"
******
Queue is FULL !!!
No insertion allowed further.
******
";
return;
}
a[rear] = i;
rear++;
}
int queue::remove()
{
if(isempty())
{
cout<<"
******
Queue Empty !!!
Value returned will be garbage.
******
";
return (-9999);
}
return(a[front++]);
}
int queue::isempty()
{
if(front == rear)
return 1;
else
return 0;
}
int queue::isfull()
{
if(rear == SIZE)
return 1;
else
return 0;
}
void main()
{
clrscr();
queue q;
q.insert(1);
q.insert(2);
cout<<"
"<<q.remove();
cout<<"
"<<q.remove();
cout<<"
"<<q.remove();
getch();
}
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