Labs' Experiences

        This blog I want to talk about the labs’ experiences and changes through the weeks. As I said before, I felt difficult in dealing with the problems of labs in beginning weeks. I thought there are two reasons. The significant problem is that I was not familiar with context. I did not read the readings and review the slides with codes before the lab. The other problem is communication because I did not know how to communicate with the partner. Luckily, these two troubles are all solved through the weeks. I knew that I should read the readings and review the example codes for preparing. Also, this habit helps me catch up with the context we learn from the previous week. In addition, I made a good friend, who is also the partner with me for working labs’ problem. We can discuss the questions about CSC and prepare for the tests. All in all, the labs are valuable and I really learn from them.  

Assignment Two

For the assignment two, I work with new people. One of them is really good at coding and I never see someone who has that clear thought in planning code. The Part one is pretty easy because we only need to create __init__, __repr__, and __eq__. When we done the analyse, we done the part one.

Compare to part one, part two is complicated. However, honestly, it is much easier than assignment one for me. There are four main functions we need in regex_functions and we write some help functions. For instance, we test string s symbols and three types of forms separately in using four help functions. Then, we write in_regex to connect fours. The other example is writing function permutation to help all_regex_permutation.

        These good thoughts are all come from my excellent partner. I really want to learn from him and do well in CS.

Linked Lists

        These two weeks focus on linked list, a recursive date structure, which is consisted of nodes and each node have a reference to the next.

        From the picture below, we can see the linked list has two parts: head, the first element of the liked list and rest, another LinkedList that has the same structure. N the class LinkedList, we need to check whether head or rest is None. If both of heaf and rest are None, the self is empty. If not, we give the value of head to self.head. Then we assign the rest is an empty LinkedList if the rest is None; otherwise, we put self.rest = rest. In addition, method prepend is for adding new item to the front of its self and ,ethod decapitate is for deleting item from self by using del. The method __getitem__ clearly shows the recursion. Using ind = ind – 1 to get the item by going deep into the rest.

       The importance of this type list is collection. For instance, the first node in the list can refer to the whole list. 

Recursion

        This is the second time I write the blog that is about Recursion. Throughout the continuous learning according to this topic, I am more familiar with it. Besides knowing what it is, I learn how to use it now.

        A1 gives us the opportunity for practicing of using recursion. We need to solve the challenging problem by applying the structure of recursion. Also, it is very helpful to work with classmates. We can help each other on working it. 

        In addition, “Tree” is the good example. Form the structure of Tree, it is really like a family. There is a root, which is also the original parent and its children also have their children. In the methods of Tree, all returns are only one line owing to comprehensive and they clearly show the abstract solution. For example, count is the method for counting the nodes in the Tree. The function is “return 1 + sum([count(n) for n in t.children]). It counts all the parents and leafs. If the n is also the parents, it needs to call the function itself. Also, we could use the structure of Tree to do the calculation: preorder, inorder and postorder.

        Recursion is very important. The main benefits are these two: firstly, the program using recursion functions is obviously clearer, simpler, shorter, and easier to understand. Secondly, it directly reflects the algorithm. All in all, I prefer recursion to iteration.