COS226

• Syllabus
• Lectures
• Precepts
• Assignments
• Quizzes
• Exams
• Help

Lectures

This table contains links to the lecture slides.

#	DATE	SLIDES	SECTION	STUDY	DEMOS
1	Tuesday 9/1	Introduction    Union–Find	1.5	guide	Quick-find Quick-union Weighted quick-union
2	Thursday 9/3	Analysis of Algorithms	1.4	guide	–
3	Tuesday 9/8	Stacks and Queues	1.3	guide	Function-call stack
4	Thursday 9/10	Advanced Java	–	guide	–
5	Tuesday 9/15	Elementary Sorts	2.1	guide	Selection sort Insertion sort Binary search
6	Thursday 9/17	Mergesort	2.2	guide	Merging
7	Tuesday 9/22	Quicksort	2.3	guide	2-way partitioning 3-way partitioning Quickselect
8	Thursday 9/24	Priority Queues	2.4	guide	Heap operations Heapsort
9	Tuesday 9/29	Elementary Symbol Tables    BSTs	3.1 3.2	guide guide	BST operations
10	Thursday 10/1	Geometric Applications of BSTs	–	guide	Line segment intersection Kd trees
11	Tuesday 10/6	Balanced Search Trees	3.3	guide	2–3 trees Red–black BSTs
12	Thursday 10/8	Hash Tables	3.4	guide	Linear probing
13	Thursday 10/15	Midterm Review	McGraw study guide
14	Tuesday 10/20	Graphs and Digraphs I	4.1 4.2	guide	Directed DFS Directed Paths Undirected DFS
15	Thursday 10/22	Graphs and Digraphs II	4.1 4.2	guide	Directed BFS Topological sort
16	Tuesday 10/27	Minimum Spanning Trees	4.3	guide	Kruskal Prim
17	Thursday 10/29	Shortest Paths	4.4	guide	Bellman–Ford Dijkstra
18	Tuesday 11/3	Dynamic Programming	IntroCS	guide	–
19	Thursday 11/5	Maxflows and Mincuts	6.4	guide	Ford–Fulkerson
20	Tuesday 11/10	String Sorts	5.1	guide	Key-indexed counting
21	Thursday 11/12	Tries	5.2	guide	Tries Ternary search tries
22	Tuesday 11/17	Data Compression	5.5	guide	Huffman LZW
23	Thursday 11/19	Algorithm Design	–	guide	–
24	Tuesday 11/24	no lecture	–		–

Readings. All readings refer to Algorithms, 4th edition by R. Sedgewick and K. Wayne unless otherwise specified.

Zoom etiquette. Here is some guidance on using Zoom during lecture.

• Please turn on your camera unless you have an unexpected difficulty or have arranged with us otherwise. Being able to see your classmates not only helps build a sense of community in the class but also sends nonverbal feedback to your instructor.

• Feel free to use a simple Zoom background.

• Mute your audio (unless you are asking or answering a question).

• To ask a synchronous question during lecture, use the Raise My Hand feature in Zoom. Unmute your audio.

• To ask an asynchronous question during lecture, use Ed Discussion. Our course staff will monitor this channel try to answer questions as they are asked.

• Sometimes we will put you in Breakout Rooms to answer or discuss questions with classmates. Turn on your camera and microphone. Participate, don't be shy! In addition to learning, it's also a brief opportunity to meet someone new, who could become a study partner.

• Protip: if possible, connect your computer directly to your router (via an Ethernet cable) to reduce latency.

Lecture recordings. We will record lectures and post them in Canvas to ensure that they are available to students regardless of their geographic location and time zone. You may choose to “opt out” of any recording in which you appear; contact the course staff immediately after the lecture so that we can edit the recording prior to posting. You may not post recordings of this class online or share them with anyone other than students enrolled in this course.

Study guide. Associated with each lecture is a study guide, which summarizes the most important topics and ideas from the lecture. It also includes optional (and ungraded) exercises.

• C level: requires that you be able to carry out the algorithm mechanically. Similar to many of the Quizzera quizzes.
• B level: requires that you really understand what is going on. The exams will have plenty of these.
• A level: requires deep comprehension, involves clever tricks, covers tangential material (or perhaps even all three).

Advice. In general, slides are intended for the lecture presentations and do not provide thorough descriptions of the material alone; for reference, read the corresponding sections from Algorithms, 4th edition. An effective strategy is to skim the textbook before the lecture, read it thoroughly soon afterwards, and complete the corresponding Quizzera quiz (and perhaps some additional B-level exercises from the study guide).

iClicker policy. Using iClicker Reef during lecture counts towards the participation component of your course grade. Using a classmate’s iClicker Reef during lecture (or allowing someone else to use your iClicker Reef during lecture) is prohibited.

Errata. Here is a list of known errors in the lecture slides and textbook.