Program In C++ about Circular Queue

GeNeRaL Circular Queue


#include<iostream.h>
#include<conio.h>
int front,rear;
int ch,val;
char op;
const int MAX = 5;
int a[MAX];
void insert(int val)
{
if((front==0 && rear==MAX-1) || (rear+1==front))
cout<<" Circular Queue is Full";
else
{
if(rear==MAX-1)
rear=0;
else
rear++;
a[rear]=val;
}
if(front==-1)
front=0;
}
int deletion()
{
int k;
if(front==-1)
cout<<"Circular Queue is Empty";
else
{
k=a[front];
if(front==rear)
front=rear=-1;
else
{
if(front==MAX-1)
front=0;
else
front++;
}
}
return k;
}
void display()
{
int i;
if(front==-1)
cout<<"Circular Queue is Empty";
else
{
if(rear < front)
{
for(i=front;i<=MAX-1;i++)
cout<<a[i]<<"   ";
for(i=0;i<=rear;i++)
cout<<a[i]<<"   ";
}
else
{
for(i=front;i<=rear;i++)
cout<<a[i]<<"   ";
cout<<endl;
}
}
}
main()
{
front=rear=-1;
do
{
clrscr();
cout<<"---------(Menu)-----------";
cout<<"\n1.|Insertion|\n2.|Deletion|\n3.|Display|\n4.|Exit|\n";
cout<<"--------------------------";
cout<<"\nEnter Your Choice <1..4> ?";
cin>>ch;
switch(ch)
{
case 1 : cout<<"Enter Element to Insert ?";
cin>>val;
insert(val);
break;
case 2 : deletion();
cout<<"Deleted Element :"<<val<<endl;
break;
case 3 : display();
break;
}
cout<<"Do you want to continue<Y/N> ?";
cin>>op;
}while(op=='Y' || op=='y');
getch();
}