Practical No: -11
Experiment No. 11: Queues are frequently used in computer programming, and a typical example is
the creation of a job queue by an operating system. If the operating system does not use priorities,
then the jobs are processed in the order they enter the system. Write C++ program for simulating job
queue. Write functions add job and delete job from queue.
Code:
using namespace std;
#include<iostream>
#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
#define SIZE 5
void enqueue(int x);
void dequeue();
void display();
int FRONT=-1;
int REAR=-1;
int QUEUE[SIZE];
main()
{
int x,ch;
while(1)
{
cout<<"\n 1:Add Job";
cout<<"\n 2:Delete Job";
cout<<"\n 3:Display";
cout<<"\n 4:Exit";
cout<<"\n Enter Your Choice:";
cin>>ch;
switch(ch)
{
case 1:
cout<<"Enter Job:";
cin>>x;
enqueue(x);
break;
case 2:
dequeue();
break;
case 3:
display();
break;
case 4:
exit(0);
}
}
getch();
}
void enqueue(int x)
{
if(REAR>=SIZE-1)
cout<<"Queue is Overflow";
else
{
REAR=REAR+1;
QUEUE[REAR]=x;
if(FRONT==-1)
FRONT=0;
}
}
void dequeue()
{
if(FRONT==-1)
cout<<"Queue is Underflow";
else
{
cout<<"Deleted Element is:"<<QUEUE[FRONT];
if(FRONT==REAR)
{
FRONT=-1;
REAR=-1;
}
else
{
FRONT=FRONT+1;
}
}
}
void display()
{
int i;
if(FRONT==-1)
cout<<"Queue is Empty \n";
else
{
for(i=FRONT;i<=REAR;i++)
cout<<""<<QUEUE[i];
}
}
O/p
add 11
delete 12
display
