void list::addnode(node* newnode)
{
 node* transverse = rootptr;
 node* temp;
 if(rootptr == NULL)
 {
  rootptr = newnode;
  return;
 }
 if(rootptr->getnextnode() == NULL)
 {
  rootptr->setnextnode(newnode);
  return;
 }
 while(transverse->getnextnode() != NULL)
 {
  transverse = transverse->getnextnode();
 }
 transverse->setnextnode(newnode);
};