PPT-CMPT 225 Algorithm Analysis: Big O Notation

Objectives Determine the running time of simple algorithms Best case Average case Worst case Profile algorithms Understand O notations mathematical basis Use O notation to measure running time. Consider the coordinate system illustrated in Figure 1 Instead of using the typical axis labels and we use and or 1 The corresponding unit basis vectors are then and or 1 The basis vectors and have the following properties 1 1 0 2 Figu Introduction to Operating Systems. . Introduction to Deadlocks. Acknowledgement: some slides are taken from Anthony D. Joseph’s course material at UC Berkeley . and Dr. Janice Reagan’s course material at SFU. B. . Steensgaard: . Points-to Analysis in Almost Linear Time. .. POPL 1996. M. Hind. : . Pointer analysis: haven't we solved this problem yet. ?.  . PASTE 2001. Presented by Ronnie . Barequet. 23.03.14. Keyang. He. Discrete Mathematics. Basic Concepts. Algorithm . – . a . specific set of instructions for carrying out a procedure or solving a problem, usually with the requirement that the procedure terminate at some point. Algorithm. Input. Output. 1. Analysis of Algorithms. How long does this take to open 1) know 2) don’t know. . Analysis of Algorithms. 2. If know combination O(n) . where n is number of rings. . If the alphabet is size m, O(nm). . Operating Systems. Processes. Multiprogramming. When multiple programs share the same processor . An example of . pseudoparallelism. Processes share processor (each get a short turn) so that in a perceptible length of time it appears processes run in parallel . dave@create.aau.dk. Source. Chapter 3 of. Cormen. , T. H., . Leiserson. , C. E., . Rivest. , R. L. and Stein, C. (2001). . Introduction to Algorithms. (Second Edition). MIT Press, Cambridge, MA.. Introduction. . Mutual Exclusion. © Janice Regan, CMPT 300, 2007-2016 . 1. Implementation. Now we have the basic ideas we need. How do we actually implement mutual exclusion?. There are several approaches. Interrupt disabling. Honors Environmental Science. Ms. . Sipe. Scientific Notation. Scientific notation expresses . very large or very small numbers . as a multiple of 2 . numbers; Based on powers of 10 . . Ex. . 6 x . February 7. , 2012. Prof. Rodger. Announcements. Read for next time Chap. 3.1-3.3. Homework 3 due Tuesday. We’ll finish . Chapter 2 first today. Chap. 3.1 Algorithms. Definition. : An . algorithm. algorithm. is a sequence of instructions . that one . must perform in order to solve a . well formulated . problem. .. Algorithm vs. Program. • An algorithm is an “abstract” description of a. process . Today’s Lecture. Algorithm . Analysis. Asymptotic analysis. bigO. notation. Project 1. Checkpoint 1 due at 11:30 pm. Submit only the files listed in the deliverables section. If you submit as a group, make sure all files have both team names. Assorted minutiae. HW1P1 due tonight at midnight. HW1P2 due Friday at midnight. HW2 out tonight. Second Java review session: . Friday 10:30 – ARC 147. Today’s Schedu. le. Algorithm Analysis, cont.. the execution time required or. the space used in memory or in disk by an algorithm . Big O notation is used describe the rough estimate of the number of “steps” to complete the algorithm. Definition.