Queue Implementation Using Array

Queue is an another Abstract Data Type, where insertion and deletion can be performed from the one end. In Queue Data Structure, the elements are inserted and deleted in the First in First Out fashion.

In Queue, the insertion is done using rear and deletion is performed through front

Applications of Queue

1. Network Programming
2. Operating System
3. Process Scheduling
4. Waiting Queue
5. Access the Shared resource (printer)
6. Multiprograming

Basic Operation of Queue

• EnQueue Operation (Insert the data)
• DeQueue Operation (Deletion of data)

EnQueue Operation

DeQueue Operation

Queue Implementation

1. Array Implementation
2. Linked List Implementation

Array Implementation of Queue

#include
#include
int max=10;
int a[10];
int front=-1,rear=-1;

void Inqueue()
{
if(rear==max)
printf("Queue is full");
else
{
int n;
if(front=-1)
front=0;
rear=rear+1;
printf("Insert the data\n");
scanf("%d",&n);
a[rear]=n;
printf("Insertion is sucessfull:%d",rear);
}
}

void Dequeue()
{
if(front==-1 || front>rear)
printf("Queue is empty");
else
{
printf("Dequeue elements are:%d\n",a[front]);
front=front+1;
}
}

void display()
{
if(front==-1)
printf("queue is empty");
else
{
int i;
for(i=front;i<=rear;i++)
{
front=front+1;
printf("\nQueue elements are:%d\n",a[i]);
}
}
}


int main()
{
int choice;
while(1)
{
printf("1:Inqueue operation\n");
printf("2:Dequeue Operation\n");
printf("3:Display\n");
printf("4:exit\n");
printf("-------------------------\n");
printf("enter the choice\n");
scanf("%d",&choice);
switch(choice)
{
case 1:
   Inqueue();
   break;
case 2:
   Dequeue();
   break;
case 3:
   display();
   break;
case 4:
   exit(0);
   break;
default:
   printf("invalid choice");
}
}
}

This code you can get it on below link

https://drive.google.com/open?id=0B2O8tJ9QXc-3a2hmZWlyQjJ1Rms