0

Generic Double Linked List

```
/* These are generic Functions for a Generic List
* Note:-Only Functions not including a Menu and an Interface
* You could use these Functions for your own Benefit*/
#include <iostream>
using namespace std;
template <class X> struct node{ //Template Structure
X data;
node* next;
node* prev;
};
template <class Y> void insert_first(node<Y>** l,Y elem)
{
node<Y>* Q=new node<Y>();
Q->data=elem;
Q->prev=NULL;
Q->next=*l;
*l=Q;
}
template <class Y> void print_l(node<Y>* l)//Print the List
{
while(l!=NULL)
{
cout<<l->data<<" ";
l=l->next;
}
}
template <class type> int count(node<type>* l)//Count the List
{
int counter=0;
while(l!=NULL)
{
counter++;
l=l->next;
}
return counter;
}
template <class type> void append(node<type>** l,type elem)
{
if(*l==NULL)
insert_first(&*l,elem);
else
{
node<type>*temp=*l;
node<type> *Q=new node<type>;
Q->data=elem;
while(temp->next!=NULL)
{
temp=temp->next;
}
temp->next=Q;
Q->prev=temp;
}
}
template <class type>
void insert_at_pos(node<type> **l,int pos,type elem)
{
if(pos<=0||pos>count(*l))
{
cout<<"Invalid Position"<<endl;
exit(1);
}
node<type>* Q=new node<type>;
node<type>* temp=*l;
int i=2;
if(pos==1)
{
insert_first(&*l,elem);
}
else
{
while(temp!=NULL)
{
if(pos==i)
{
Q->data=elem;
Q->next=temp->next;
Q->prev=temp;
temp->next=Q;
}
i++;
temp=temp->next;
}
}
}
int main(int argc, char** argv)
{
node<int>* q=NULL;//Create Empty Pointer that Will point to the Head of the List
insert_first(&q,2);
insert_at_pos(&q,2,2);
return 0;
}
```

If there is any critique about this code plz tell me about it to be careful in the next time i write any code .