Finding endpoints

We have created three nodes: one containing eggs, one ham, and another spam. The eggs node points to the ham node, which in turn points to the spam node. But what does the spam node point to? Since this is the last element in the list, we need to make sure its next member has a value that makes this clear.

If we make the last element point to nothing then we make this fact clear. In python, we will use the special value None to denote nothing:

The last node has its next point pointing to None. As such it is the last node in the chain of nodes.

Node

Here is a simple node implementation of what we have discussed so far:

    class Node: 
        def __init__(self, data=None): 
            self.data = data 
            self.next = None 

Note

Do not confuse the concept of a node with Node.js, a server-side technology implemented in JavaScript.

The next pointer is initialized to None, meaning that unless you change the value of next, the node is going to be an end-point. This is a good...