PROGRAM 15

Date: 25/08/2015

Write a Menu Driven program to do insertion, deletion and display the elements in a Linear Circular Queue.

SOURCE CODE

#include<iostream.h>#include<conio.h>#include<stdio.h>#include<stdlib.h>struct student{

int rollno;char name[30];float marks;

};void enter(student S[], int i){

clrscr();

cout<<"ENTER ROLL NUMBER :- ";cin>>S[i].rollno;cout<<"ENTER NAME :- ";gets(S[i].name);cout<<"ENTER MARKS :- ";cin>>S[i].marks;

}void display(student S[], int j){

cout<<S[j].rollno<<" "<<S[j].name<<" "<<S[j].marks<<endl;}void insert_cq(student S[], int n , int&rear , int &front){

clrscr();

if((rear==n-1 &&front==0) || (rear==front+1)){

cout<<"QUEUE FULL ";}else if(rear==-1){

rear++; front=0;enter(S,rear);

}else{

rear++;enter(S,rear);

}

}void deletion(student S[], int n, int &rear , int &front){

if(front==-1){

cout<<"QUEUE IS EMPTY";}else if(rear==front){ display(S,front); front=-1; rear=-1;

}else if(front==n-1){

display(S,front);front=0;

}else{

display(S,front);front++;

}}void display_cq(student S[], int n, int rear, int front){

clrscr();if(front==-1){

cout<<"Queue is Empty";}else if(front<=rear){

for(int i=0; i<=rear; i++){

display(S,i);}

}else{

for(int i=front; i<n; i++)display(S,i);

for(int j=0; j<=rear; j++)display(S,j);

}}void main(){

clrscr();

student S[20]; int n,rear=-1,front=-1;

cout<<"Enter the number of students :- ";cin>>n;

clrscr();

int choice=0;

while(choice!=4){

clrscr();

gotoxy(3,3);cout<<"CIRCULAR QUEUE OPERATION";gotoxy(4,4);cout<<"1. INSERT";gotoxy(5,5);cout<<"2. DELETE";gotoxy(6,6);cout<<"3. DISPLAY ";gotoxy(7,7);cout<<"4. EXIT";

gotoxy(4,8);cout<<"Enter your Choice :- ";cin>>choice;

switch(choice){

case 1:clrscr();insert_cq(S,n,rear,front);getch();break;

case 2:clrscr();deletion(S,n,rear,front);getch();break;

case 3:clrscr();display_cq(S,n,rear,front);getch();break;

case 4:clrscr();cout<<"TERMINATING PROGRAM";exit(0);break;

default:cout<<"INVALID CHOICE";getch();

}}getch();

}

OUTPUT

e