C++ Programming Code Examples
C++ > Data Structures Code Examples
C++ Program to Implement Sorted Circularly Doubly Linked List
/* C++ Program to Implement Sorted Circularly Doubly Linked List
This C++ program displays the nodes of a doubly linked list with the last node pointing back to the first as well as the first node pointing back to the last giving a circularly doubly linked list.
Here is the source code of the C++ program to display the values present in the nodes cyclically. */
#include<stdio.h>
#include<conio.h>
#include<iostream>
using namespace std;
struct node
{
int data;
node *next, *prev;
}*p = NULL, *head = NULL, *r = NULL, *np = NULL, *tail = NULL;
int c = 0;
void create(int x)
{
np = new node;
np->data = x;
np->next = NULL;
np->prev = NULL;
if (c == 0)
{
tail = np;
head = np;
p = head;
p->next = head;
p->prev = head;
c++;
}
else if (c == 1)
{
p = head;
r = p;
if (np->data < p->data)
{
np->next = p;
p->prev = np;
head = np;
p->next = np;
np->prev = p;
tail = p;
}
else if (np->data > p->data)
{
p->next = np;
np->prev = p;
np->next = head;
p->prev = np;
}
c++;
} else {
p = head;
r = p;
if (np->data < p->data)
{
np->next = p;
p->prev = np;
head = np;
do
{
p = p->next;
}
while (p->next != r);
tail = p;
p->next = np;
np->prev = p;
}
else if (np->data > p->data)
{
while (p->next != head && np->data > p->data)
{
r = p;
p = p->next;
if (p->next == head && (p->data < np->data))
{
p->next = np;
np->prev = p;
np->next = head;
tail = np;
head->prev = np;
break;
}
else if (np->data < p->data)
{
r->next = np;
np->prev = r;
np->next = p;
p->prev = np;
if (p->next != head)
{
do
{
p = p->next;
}
while (p->next != head);
}
tail = p;
break;
}
}
}
}
}
void traverse_tail(int i)
{
node *t = tail;
int x = 0;
while (x <= i)
{
cout<<t->data<<"\t";
t = t->prev;
x++;
}
cout<<endl;
}
void traverse_head(int i)
{
node *t = head;
int c = 0;
while (c <= i)
{
cout<<t->data<<"\t";
t = t->next;
c++;
}
cout<<endl;
}
int main()
{
int i = 0, n, x, ch;
cout<<"enter the no of nodes\n";
cin>>n;
while (i < n)
{
cout<<"\nenter value of node\n";
cin>>x;
create(x);
i++;
}
cout<<"\nTraversing Doubly Linked List head first\n";
traverse_head(n);
cout<<"\nTraversing Doubly Linked List tail first\n";
traverse_tail(n);
getch();
}
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