- #include<iostream>
- using namespace std;
- int cqueue[5];
- int front=-1,rear=-1,n=5;
- void insertcq(int val)
- {
- if((front==0 && rear==n-1)||(front==rear+1))
- {
- cout<<"queue overflow";
- return;
- }
- if(front==-1)
- {
- front=0;
- rear=0;
- }
- else
- {
- if(rear==n-1)
- rear=0;
- else
- rear=rear+1;
- }
- cqueue[rear]=val;
- }
- void deletecq()
- {
- if(front==-1)
- {
- cout<<"queue underflow\n";
- return;
- }
- cout<<"element deleted from queue is:"<<cqueue[front]<<endl;
- if(front==rear)
- {
- front==-1;
- rear==-1;
- }
- else
- {
- if(front==n-1)
- front=0;
- else
- front=front+1;
- }
- }
- void displaycq()
- {
- 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<<cqueue[f]<<" ";
- f++;
- }
- }
- else
- {
- while(f<=n-1)
- {
- cout<<cqueue[f]<<" ";
- f++;
- }
- f=0;
- while(f<=r)
- {
- cout<<cqueue[f]<<" ";
- f++;
- }
- }
- cout<<endl;
- }
- int main()
- {
- int ch,val;
- cout<<"1. insert\n";
- cout<<"2. delete\n";
- cout<<"3. display\n";
- cout<<"4. exit\n";
- do
- {
- cout<<"enter choice:"<<endl;
- cin>>ch;
- switch(ch)
- {
- case 1:
- cout<<"input for insertion:"<<endl;
- cin>>val;
- insertcq(val);
- break;
- case 2:
- deletecq();
- break;
- case 3:
- displaycq();
- break;
- case 4:
- cout<<"exit\n";
- break;
- default:
- cout<<"incorrect";
- }
- }
- while (ch!=4);
- return 0;
- }