I need the Code to automatically create nodes and add them in order to the list.
ID: 3763261 • Letter: I
Question
I need the Code to automatically create nodes and add them in order to the list.
Code:
#include<iostream>
#include<cstdio>
#include<cstdlib>
// Node Declaration
using namespace std;
struct node
{
int info;
struct node *next;
struct node *prev;
}*start;
//Class Declaration
class double_llist
{
public:
void create_list(int value);
void add_begin(int value);
void add_after(int value, int position);
void delete_element(int value);
void search_element(int value);
void display_dlist();
void count();
void reverse();
double_llist()
{
start = NULL;
}
};
//Main: Conatins Menu
int main()
{
int choice, element, position;
double_llist dl;
while (1)
{
cout<<" Doubly linked list "<<endl;
cout<<"--------------------"<<endl;
cout<<endl<<"1.Create Node"<<endl;
cout<<"2.Add at begining"<<endl;
cout<<"3.Add after position"<<endl;
cout<<"4.Delete"<<endl;
cout<<"5.Display"<<endl;
cout<<"6.Count"<<endl;
cout<<"7.Reverse"<<endl;
cout<<"8.Quit"<<endl;
cout<<"Enter your choice : ";
cin>>choice;
switch ( choice )
{
case 1:
cout<<"Enter the element: ";
cin>>element;
dl.create_list(element);
cout<<endl;
break;
case 2:
cout<<"Enter the element: ";
cin>>element;
dl.add_begin(element);
cout<<endl;
break;
case 3:
cout<<"Enter the element: ";
cin>>element;
cout<<"Insert Element after postion: ";
cin>>position;
dl.add_after(element, position);
cout<<endl;
break;
case 4:
if (start == NULL)
{
cout<<"List empty,nothing to delete"<<endl;
break;
}
cout<<"Enter the element for deletion: ";
cin>>element;
dl.delete_element(element);
cout<<endl;
break;
case 5:
dl.display_dlist();
cout<<endl;
break;
case 6:
dl.count();
break;
case 7:
if (start == NULL)
{
cout<<"List empty,nothing to reverse"<<endl;
break;
}
dl.reverse();
cout<<endl;
break;
case 8:
exit(1);
default:
cout<<"Wrong choice"<<endl;
}
}
return 0;
}
//Create Double Link List
void double_llist::create_list(int value)
{
struct node *s, *temp;
temp = new(struct node);
temp->info = value;
temp->next = NULL;
if (start == NULL)
{
temp->prev = NULL;
start = temp;
}
else
{
s = start;
while (s->next != NULL)
s = s->next;
s->next = temp;
temp->prev = s;
}
}
//Insertion at the beginning
void double_llist::add_begin(int value)
{
if (start == NULL)
{
cout<<"First Create the list."<<endl;
return;
}
struct node *temp;
temp = new(struct node);
temp->prev = NULL;
temp->info = value;
temp->next = start;
start->prev = temp;
start = temp;
cout<<"Element Inserted"<<endl;
}
// Insertion of element at a particular position
void double_llist::add_after(int value, int pos)
{
if (start == NULL)
{
cout<<"First Create the list."<<endl;
return;
}
struct node *tmp, *q;
int i;
q = start;
for (i = 0;i < pos - 1;i++)
{
q = q->next;
if (q == NULL)
{
cout<<"There are less than ";
cout<<pos<<" elements."<<endl;
return;
}
}
tmp = new(struct node);
tmp->info = value;
if (q->next == NULL)
{
q->next = tmp;
tmp->next = NULL;
tmp->prev = q;
}
else
{
tmp->next = q->next;
tmp->next->prev = tmp;
q->next = tmp;
tmp->prev = q;
}
cout<<"Element Inserted"<<endl;
}
// Deletion of element from the list
void double_llist::delete_element(int value)
{
struct node *tmp, *q;
//first element deletion
if (start->info == value)
{
tmp = start;
start = start->next;
start->prev = NULL;
cout<<"Element Deleted"<<endl;
free(tmp);
return;
}
q = start;
while (q->next->next != NULL)
{
//Element deleted in between
if (q->next->info == value)
{
tmp = q->next;
q->next = tmp->next;
tmp->next->prev = q;
cout<<"Element Deleted"<<endl;
free(tmp);
return;
}
q = q->next;
}
//last element deleted
if (q->next->info == value)
{
tmp = q->next;
free(tmp);
q->next = NULL;
cout<<"Element Deleted"<<endl;
return;
}
cout<<"Element "<<value<<" not found"<<endl;
}
// Will display elements of Doubly Link List
void double_llist::display_dlist()
{
struct node *q;
if (start == NULL)
{
cout<<"List empty,nothing to display"<<endl;
return;
}
q = start;
cout<<"The Doubly Link List is :"<<endl;
while (q != NULL)
{
cout<<q->info<<" <-> ";
q = q->next;
}
cout<<"NULL"<<endl;
}
// Number of elements in Doubly Link List
void double_llist::count()
{
struct node *q = start;
int cnt = 0;
while (q != NULL)
{
q = q->next;
cnt++;
}
cout<<"Number of elements are: "<<cnt<<endl;
}
// Reverse Doubly Link List
void double_llist::reverse()
{
struct node *p1, *p2;
p1 = start;
p2 = p1->next;
p1->next = NULL;
p1->prev = p2;
while (p2 != NULL)
{
p2->prev = p2->next;
p2->next = p1;
p1 = p2;
p2 = p2->prev;
}
start = p1;
cout<<"List Reversed"<<endl;
}
Explanation / Answer
Answer:
#include<iostream>
#include<cstdio>
#include<cstdlib>
// Node Declaration
using namespace std;
struct node
{
int info;
struct node *next;
struct node *prev;
}*start;
//Class Declaration
class double_llist
{
public:
void create_list(int value);
void add_begin(int value);
void add_after(int value, int position);
void delete_element(int value);
void search_element(int value);
void sort();
void display_dlist();
void count();
void reverse();
double_llist()
{
start = NULL;
}
};
//Main: Conatins Menu
int main()
{
int choice, element, position;
double_llist dl;
while (1)
{
cout<<" Doubly linked list "<<endl;
cout<<"--------------------"<<endl;
cout<<endl<<"1.Create Node"<<endl;
cout<<"2.Add at begining"<<endl;
cout<<"3.Add after position"<<endl;
cout<<"4.Delete"<<endl;
cout<<"5.Display"<<endl;
cout<<"6.Count"<<endl;
cout<<"7.Sort " << endl;
cout<<"8.Reverse"<<endl;
cout<<"9.Quit"<<endl;
cout<<"Enter your choice : ";
cin>>choice;
switch ( choice )
{
case 1:
cout<<"Enter the element: ";
cin>>element;
dl.create_list(element);
cout<<endl;
break;
case 2:
cout<<"Enter the element: ";
cin>>element;
dl.add_begin(element);
cout<<endl;
break;
case 3:
cout<<"Enter the element: ";
cin>>element;
cout<<"Insert Element after postion: ";
cin>>position;
dl.add_after(element, position);
cout<<endl;
break;
case 4:
if (start == NULL)
{
cout<<"List empty,nothing to delete"<<endl;
break;
}
cout<<"Enter the element for deletion: ";
cin>>element;
dl.delete_element(element);
cout<<endl;
break;
case 5:
dl.display_dlist();
cout<<endl;
break;
case 6:
dl.count();
break;
case 7:
dl.sort();
break;
case 8:
if (start == NULL)
{
cout<<"List empty,nothing to reverse"<<endl;
break;
}
dl.reverse();
cout<<endl;
break;
case 9:
exit(1);
default:
cout<<"Wrong choice"<<endl;
}
}
return 0;
}
//Create Double Link List
void double_llist::create_list(int value)
{
struct node *s, *temp;
temp = new(struct node);
temp->info = value;
temp->next = NULL;
if (start == NULL)
{
temp->prev = NULL;
start = temp;
}
else
{
s = start;
while (s->next != NULL)
s = s->next;
s->next = temp;
temp->prev = s;
}
}
//Insertion at the beginning
void double_llist::add_begin(int value)
{
if (start == NULL)
{
cout<<"First Create the list."<<endl;
return;
}
struct node *temp;
temp = new(struct node);
temp->prev = NULL;
temp->info = value;
temp->next = start;
start->prev = temp;
start = temp;
cout<<"Element Inserted"<<endl;
}
// Insertion of element at a particular position
void double_llist::add_after(int value, int pos)
{
if (start == NULL)
{
cout<<"First Create the list."<<endl;
return;
}
struct node *tmp, *q;
int i;
q = start;
for (i = 0;i < pos - 1;i++)
{
q = q->next;
if (q == NULL)
{
cout<<"There are less than ";
cout<<pos<<" elements."<<endl;
return;
}
}
tmp = new(struct node);
tmp->info = value;
if (q->next == NULL)
{
q->next = tmp;
tmp->next = NULL;
tmp->prev = q;
}
else
{
tmp->next = q->next;
tmp->next->prev = tmp;
q->next = tmp;
tmp->prev = q;
}
cout<<"Element Inserted"<<endl;
}
// Deletion of element from the list
void double_llist::delete_element(int value)
{
struct node *tmp, *q;
//first element deletion
if (start->info == value)
{
tmp = start;
start = start->next;
start->prev = NULL;
cout<<"Element Deleted"<<endl;
free(tmp);
return;
}
q = start;
while (q->next->next != NULL)
{
//Element deleted in between
if (q->next->info == value)
{
tmp = q->next;
q->next = tmp->next;
tmp->next->prev = q;
cout<<"Element Deleted"<<endl;
free(tmp);
return;
}
q = q->next;
}
//last element deleted
if (q->next->info == value)
{
tmp = q->next;
free(tmp);
q->next = NULL;
cout<<"Element Deleted"<<endl;
return;
}
cout<<"Element "<<value<<" not found"<<endl;
}
// Will display elements of Doubly Link List
void double_llist::display_dlist()
{
struct node *q;
if (start == NULL)
{
cout<<"List empty,nothing to display"<<endl;
return;
}
q = start;
cout<<"The Doubly Link List is :"<<endl;
while (q != NULL)
{
cout<<q->info<<" <-> ";
q = q->next;
}
cout<<"NULL"<<endl;
}
// Number of elements in Doubly Link List
void double_llist::count()
{
struct node *q = start;
int cnt = 0;
while (q != NULL)
{
q = q->next;
cnt++;
}
cout<<"Number of elements are: "<<cnt<<endl;
}
// Reverse Doubly Link List
void double_llist::reverse()
{
struct node *p1, *p2;
p1 = start;
p2 = p1->next;
p1->next = NULL;
p1->prev = p2;
while (p2 != NULL)
{
p2->prev = p2->next;
p2->next = p1;
p1 = p2;
p2 = p2->prev;
}
start = p1;
cout<<"List Reversed"<<endl;
}
void double_llist:: sort() {
struct node *curr;
struct node *temp;
for(bool didSwap = true; didSwap; ) {
didSwap = false;
temp = start->next;
for(curr = start->next; curr->next != NULL; curr = curr->next) {
if(curr->info > curr->next->info) {
if (start == curr) {
start = curr->next;
curr->next = start->next;
start->next = curr;
temp = start;
} else {
temp->next = curr->next;
curr->next = temp->next->next;
temp->next->next = curr;
}
didSwap = true;
} else if (start != curr) {
temp = temp->next;
}
}
}
}