Enqueue,Dequeue,Display c++ cpp

queue.cpp

/******************************************************
             QUEUE C++
             AUTHOR URI:https://mostafa.itnishi.com
 ******************************************************/
#include<iostream>
#include<conio.h>
#include<stdlib.h>
#define SIZE 5
using namespace std;
int q[SIZE],front=0,rear=0;
int main()
{
int ch;
void enqueue();
void dequeue();
void display();

while(1)
{
cout<<"\n 1. add element";
cout<<"\n 2. remove element";
cout<<"\n 3.display";
cout<<"\n 4.exit";
cout<<"\n enter your choice:";
cin>>ch;

switch(ch)
{
case 1:
enqueue();
break;
case 2:
dequeue();
break;
case 3:
display();
break;
case 4:
exit(0);
default:
cout<<"\n invalid choice";
}
}
}
void enqueue()
{
int no;
if (rear==SIZE && front==0)
cout<<"queue is full";
else
{
cout<<"enter the num:";
cin>>no;
q[rear]=no;
}
rear++;
}
void dequeue()
{
int no,i;
if (front==rear)
cout<<"queue is empty";
else
{
no=q[front];
front++;
cout<<"\n"<<no<<" -removed from the queue\n";
}
}
void display()
{
int i,temp=front;
if (front==rear)
cout<<"the queue is empty";
else
{
cout<<"\n element in the queue:";
for(i=temp;i<rear;i++)
{
cout<<q[i]<<" ";
}
}
}

queue2.cpp

/******************************************************
             QUEUE C++
             AUTHOR URI:https://mostafa.itnishi.com
 ******************************************************/
    #include<iostream>
    #define maxi 1000
    using namespace std;
    class qqueue{
        int a[maxi];
        int f,r;
        public:
        void initialize();
        void enqueue(int val);
        void dequeue();
        void display();
    };
    void qqueue::initialize(){
        cout<<"Empty Queue is created :D";
        f=r=-1;
    }
    void qqueue::enqueue(int val){
        if(r==maxi-1){
            cout<<"\nQueue Overflow..";
        }
        else if(f==-1 && r==-1){
            f=r=1;
            a[r]=val;
        }
        else{
            r++;
            a[r]=val;
        }
    }
    void qqueue::dequeue(){
        if(f==-1 && r==-1){
            cout<<"\nQueue is already empty..";
        }
        else if(f==r){
            cout<<"\nThe dequeued element is.."<<a[f];
            f=r=-1;
        }
        else{
            cout<<"\nThe dequeued element is.."<<a[f];
            f++;
        }
    }
    void qqueue::display(){
        int x;
        if(f==-1 && r==-1){
            cout<<"\nThe Queue is empty..";
            return;
        }
        cout<<"\nThe Contents of the Queue is..";
        for(x=f;x<=r;x++){
            cout<<a[x]<<" ";
        }
    }
    int main()
    {
        qqueue q;
        q.initialize();
        int ch,val;
        cout<<"\nChoice: \n1)Enqueue \n2)Dequeue \n3)Display \n4)Exit";
        while(1){
            cout<<"\nEnter your choice..";
            cin>>ch;
            if(ch==1){
                cout<<"\nEnter the element to be enqueued..";
                cin>>val;
                q.enqueue(val);
            }
            else if(ch==2){
                q.dequeue();
            }
            else if(ch==3){
                q.display();
            }
            else{
                break;
            }
        }
        return 0;
    }