double linked Assignment 2 c++

c++ Double linked list 

https://www.geekboots.com/cpp/doubly-linkedlist

http://www.sanfoundry.com/cpp-program-implement-doubly-linked-list/

2nd one has better explanation.

https://codereview.stackexchange.com/questions/104487/doubly-linked-list-implementation-in-c

bool isEmpty(node *head)
{
    if(head == NULL)
        return true;
    else
        return false;
}
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bool empty( void ) const
{
  return ( this->head == 0 );
}

http://cslibrary.stanford.edu/105/LinkedListProblems.pdf