Doubly Linked List(code)

#include<iostream>
using namespace std;
class node
{
 public:
 int info;
 node *next, *prev;
}*start=NULL,*last=NULL;
void InsertAtBeg(int n)
{
 node *temp=new node;
 node *ptr=start;
 temp->info=n;
 temp->prev=NULL;
 temp->next=start;
 start=temp;
 if(ptr==NULL)
 {
 last=temp;
    }
    else
    {
    temp->next->prev=temp; 
 }
}
void Display()
{
 //cout<<"printing list in reverse order";
 //node *ptr=last;
 node *ptr=start;
 while(ptr!=NULL)
 {
 cout<<ptr->info<<"->";
 //ptr=ptr->prev;
 ptr=ptr->next;
 }
 cout<<"NULLn";
}
void InsertAtLoc(int n,int loc)
{
 node *temp=new node;
 node *ptr=start;
 node *ptr1;
 for(int i=0; i<loc-1; i++)
 {
 ptr1=ptr;
 ptr=ptr->next;
 }
 temp->info=n;
 temp->next=ptr1->next;
 temp->prev=ptr1;
 ptr1->next->prev=temp;
 ptr1->next=temp;
 
}
void InsertAtLast(int n)
{
 node *temp=new node;
 node *ptr=last;
 temp->info=n;
 temp->next=NULL;
 temp->prev=last;
 last=temp;
 if(ptr==NULL)
 {
 start=temp;
 }
 else
 {
 temp->prev->next=temp;
 }
}
void DeleteFromFirst()
{
 node *temp=start;
 temp->next->prev=NULL;
 start=temp->next;
}
void DeleteFromLast()
{
 node *temp=last;
 temp->prev->next=NULL;
 last=temp->prev;
}
void DeleteFromLoc(int loc)
{
 node *ptr=start;
 node *ptr1;
 for(int i=0; i<loc-1; i++)
 {
 ptr1=ptr;
 ptr=ptr->next;
 }
 ptr1->next=ptr->next;
 ptr->next->prev=ptr1;
}
void Search(int n)
{
 int loc=0;
 node *ptr=start;
 while(ptr!=NULL)
 {
 loc++;
 if(ptr->info==n)
 {
 cout<<"item found at location "<<loc;
 break;
 }
 else
 {
 ptr=ptr->next;
 }
 if(ptr==NULL)
 {
 cout<<"item doesn't exists in the list";
 }
 }
}
int main()
{
 InsertAtBeg(10);
 InsertAtBeg(20);
 InsertAtBeg(30);
 InsertAtBeg(40);
 InsertAtBeg(50);
 InsertAtLoc(15,5);
 InsertAtLast(5);
 DeleteFromFirst();
 DeleteFromLast();
 DeleteFromLoc(2);
 Display();
 Search(20);
 return 0;
}