Week 8

In lecture, we have talked about linked list and tree for several weeks. Generally, i think they have some similar parts; for example, the first parameter after self are all the value of that linked list or tree, and the following parameter is another linked list or tree. These two are quite organized ways to store data. Especially for linked list, it so convenient to mutate single linked list whatever it is hear, tail or in middle. Not like a regular list which is almost impossible to prepend some value without spending plenty of time. Because in linked list, prepend and pend are the same thing, they just take one step, not one step + shifting every original term in regular list.