/*WAP for implementation of Circular Queue*/
#include<iostream>
using namespace std;
class queue
{
int FRONT;
int REAR;
int MAX;
int *arr;
public:
queue()
{
cout<<"Enter the size of queue:\t";
cin>>MAX;
FRONT=-1;
REAR=-1;
arr = new int[MAX];
}
bool is_empty()
{
if (FRONT==-1)
{
return true;
}
else
{
return false;
}
}
bool is_full()
{
if (((REAR==MAX-1)&& (FRONT==0))|| (FRONT == REAR+1))
{
return true;
}
else
{
return false;
}
}
void enqueue(int num)
{
if (REAR ==-1 && FRONT==-1)
{
FRONT=0;
REAR=0;
arr[REAR]=num;
}
else if (!is_full())
{
if(REAR==MAX-1)
{
REAR=0;
}
else
{
REAR+=1;
}
arr[REAR]=num;
}
else
{
cout<<num<<"****************Overflow****************"<<endl;
}
}
int dequeue()
{
if(!is_empty())
{
int VALUE=arr[FRONT];
if (FRONT==REAR)
{
FRONT=-1;
REAR=-1;
}
else if (FRONT==MAX-1)
{
FRONT=0;
}
else
{
FRONT+=1;
}
return VALUE;
}
}
};
int main()
{
queue q;
int choice;
int num;
do
{
cout<<endl<<"Enter your choice:"<<endl;
cout<<"1)enqueue"<<endl;
cout<<"2)dequeue"<<endl;
cout<<"3)quit"<<endl;
cout<<"Enter your choice:\t";
cin>>choice;
switch(choice)
{
case 1:
cout<<"\nEnter number to enqueue:\t";
cin>>num;
q.enqueue(num);
break;
case 2:
if (!q.is_empty())
{
cout<<"\n*********Dequeued
number:"<<q.dequeue()<<"*********\n";
}
else
{
cout<<"****************Underflow****************"<<endl;
}
break;
case 3:
break;
}
}
while (choice !=3);
}
/*WAP for implementation of Circular Queue*/
#include <iostream>
#define MAX 4
using namespace std;
int front=-1,rear=-1,data,queue[MAX];
void push()
{
if ((front == 0 && rear == MAX-1) || (front == rear+1))
{
cout<<"Queue Overflow \n";
return;
}
if (front == -1 && rear==-1)
{
front = 0;
rear = 0;
}
else
{
if (rear == MAX - 1)
rear = 0;
else
rear = rear + 1;
}
cout<<"Enter value to push: ";
cin>>data;
queue[rear] = data ;
}
void pop()
{
if (front == -1)
{
cout<<"Queue Underflow\n";
return ;
}
cout<<"Element dequeued from Circural queue is : "<<queue[front]<<endl;
if (front == rear)
{
front = -1;
rear = -1;
}
else
{
if (front == MAX - 1)
front = 0;
else
front = front + 1;
}
}
void display()
{
{
int f = front, r = rear;
if (front == -1)
{
cout<<"Queue is empty"<<endl;
return;
}
cout<<"Queue elements are :\n";
if (f <= r)
{
while (f <= r)
{
cout<<queue[f]<<" ";
f++;
}
}
else
{
while (f <= MAX - 1)
{
cout<<queue[f]<<" ";
f++;
}
f = 0;
while (f <= r)
{
cout<<queue[f]<<" ";
f++;
}
}
cout<<endl;
}
}
int main()
{
int ch;
cout << "1) Insert element to circular queue" << endl;
cout << "2) Delete element from circular queue" << endl;
cout << "3) Display all the elements of ciruclar queue" << endl;
cout << "4) Exit" << endl;
do
{
cout << "Enter your choice: ";
cin >> ch;
cout<<endl;
switch (ch)
{
case 1:
push();
break;
case 2:
pop();
break;
case 3:
display();
break;
case 4:
cout << "Exit" << endl;
break;
default:
cout << "Invalid choice" << endl;
}
cout<<endl<<endl<<endl;
}
while (ch != 4);
return 0;
}
/*WAP for implementation of Circular Queue*/
#include<iostream>
#include<cstdlib>
#define capacity 4
using namespace std;
template <class X>
class Queue
{
int front1,rear;
X data[capacity];
public:
Queue():front1(-1),rear(-1) {}
void enqueue(X var)
{
if(IsQueuefull())
cout<<"queue overflow"<<endl;
else
{
rear=(rear+1)%capacity;
data[rear]=var;
if(front1 == -1)
front1 =0;
}
}
void dequeue()
{
if(IsEmptyQueue())
cout<<"queue underflow"<<endl;
else
{
cout<<"\ndequeued element is "<<data[front1]<<endl;
if(front1==rear)
front1=rear=-1;
else
front1=(front1+1)%capacity;
}
}
bool IsEmptyQueue()
{
if(front1 == -1)
return true;
else
return false;
}
bool IsQueuefull()
{
if((front1==0&&rear==capacity-1)||front1==rear+1)
return true;
else
return false;
}
int Queuesize()
{
if(IsEmptyQueue())
return 0;
else
return ((capacity-front1+rear)%capacity+1);
}
void Front()
{
if(IsEmptyQueue())
cout<<"\nQueue underflow"<<endl;
else
cout<<"\nThe front element of queue is : "<<data[front1]<<endl;
}
};
int main()
{
Queue <int> q;
int choice;
while(1)
{
cout<<"1.Enqueue\n2.Dequeue\n3.View front element\n4.Check queue
size\n5.exit\nEnter your choice ";
cin>>choice;
switch(choice)
{
case 1:
{
while(1)
{
int num;
cout<<"\nEnter -1 to finish enqueue\nEnter the value: ";
cin>>num;
if(num==-1)
break;
q.enqueue(num);
}
break;
}
case 2:
{
q.dequeue();
break;
}
case 3:
{
q.Front();
break;
}
case 4:
{
cout<<"\nQueue size is: "<<q.Queuesize();
break;
}
default:
exit(0);
}
cout<<"\n\n";
}
return 0;
}
/*WAP for implementation of Circular Queue*/
#include<iostream>
#define max 5
using namespace std;
//define a Queue //
template<class T>
class Queue
{
private:
int front,rear,counter;
T arr[max];
T sign;
public:
// constructor to initialize front and rear
Queue(T emptysign)
{
front=-1;
rear=-1;
counter=0 ;
sign=emptysign;
for(int i= 0; i<max; i++)
{
arr[i]=sign;
}
}
//isEmpty to check if queue is empty
bool isEmpty()
{
if ( counter == 0)
{
return true;
}
else
{
return false;
}
}
//to check if Queue is full
bool isFull()
{
if (counter == max)
{
return true;
}
else
{
return false;
}
}
//enqueue into Queue
void enq(T data)
{
if(!isFull())
{
if(front == -1)
front = 0;
arr[++rear % max] = data;
counter = rear - front + 1;
}
else
{
cout<<"Overflow"<<endl;
}
}
//dequeue from the Queue
void deq()
{
if(!isEmpty())
{
cout << arr[front % max] << endl;
arr[front++ % max]=sign;
counter = rear - front + 1;
}
else
{
cout<<"UnderFlow"<<endl;
}
}
//display Queue
void display()
{
cout<<"\n ==========="<<endl;
cout<<"The queue is ==>\t";
for(int i=0; i<max; i++)
{
cout<<arr[i]<<"\t";
}
cout<<"front:: "<<front%max<<"\tlen:: "<<counter<<endl;
cout<<" ===========\n"<<endl;
}
};
//driver main function
int main()
{
Queue<int> que(0);
char opt='a';
int val;
cout<<"what to do:\n"<<"d for dequeue:\n"<<"e for enqueue\n"<<"x for
display\n"<<"n for end"<<endl;
while(opt!='n')
{
cout<<"your choice: ";
cin>>opt;
switch(opt)
{
case 'd':
que.deq();
break;
case 'e':
cout<<"enter value:";
cin >> val;
que.enq(val);
break;
case 'x':
que.display();
break;
case 'n':
cout<<"thank you"<<endl;
break;
}
}
return 0;
}
