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CS233601: Discrete CS233601: Discrete MathematicsMathematics

CS233601: Discrete CS233601: Discrete MathematicsMathematics

Department of Computer ScienceDepartment of Computer ScienceNational Tsing Hua UniversityNational Tsing Hua University

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• Instructor– Shun-Ren Yang (楊舜仁 ), sryang@cs.nthu.edu.tw– Office Number: R3202, EECS Building

• Time and Location– Wednesday 10:10 ~ 12:00, Friday 11:10 ~ 12:00– EECS 236

• Office Hours– By appointment

• Textbook– "Elements of Discrete Mathematics" (McGraw-Hill), by P

rof. C. L. Liu• Reference

– "Discrete Mathematics and Its Applications" (McGraw-Hill), by Kenneth H. Rosen

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• Teaching Assistants (TAs)– 吳宗穎 , 綜二館 745, 分機 33541,

boboron@wmnet.cs.nthu.edu.tw – 林依潔 , 綜二館 745 , 分機 33541,

ada@wmnet.cs.nthu.edu.tw

• TA Office Hours– Thur. 4:20 ~6:20 pm

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What is Discrete Mathematics?

• Discrete mathematics is the part of mathematics devoted to the study of discrete objects.

• Here discrete means consisting of distinct or unconnected elements.

• The kind of problems solved using discrete mathematics include:– How many ways are there to choose a valid

password on a computer system?

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What is Discrete Mathematics? (Cont.)

– What is the probability of winning a lottery?– Is there a link between two computers in a

network?– What is the shortest path between two cities using

a transportation system?– How can a list of integers be sorted so that the

integers are in increasing order?– How many steps are required to do such a

sorting?– How can it be proved that a sorting algorithm

correctly sorts a list?

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What is Discrete Mathematics? (Cont.)

– How can a circuit that adds two integers be designed?

– How many valid Internet addresses are there?

• You will learn the discrete structures and techniques needed to solve such problems.

• More generally, discrete mathematics is used whenever objects are counted, when relationships between finite (or countable) sets are studied, and when processes involving a finite number of steps are analyzed.

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Why Study Discrete Mathematics?

• Through this course you can develop your mathematical maturity, that is, your ability to understand and create mathematical arguments.

• Discrete mathematics provides the mathematical foundations for many computer science courses, including data structures, algorithms, database theory, automata theory, formal languages, compiler theory, computer security, and operating systems.

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Five Themes in Discrete Mathematics?

• Mathematical Reasoning– Understanding mathematical reasoning in order to read,

comprehend, and construct mathematical arguments– Mathematical logic, methods of proof, mathematical induction

• Combinatorial Analysis– The ability to count or enumerate objects– The basic techniques of counting, permutations, combinations

• Discrete Structures– The abstract mathematical structures used to represent

discrete objects and relationships between these objects– Sets, permutations, relations, graphs, trees, and finite-state

machines

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Five Themes in Discrete Mathematics?

• Algorithmic Thinking– The specification of an algorithm that solves

certain classes of problems– The specification of the algorithm, the

verification of the algorithm, the analysis of the space and time complexities of the algorithm

• Applications and Modeling– Computer science, data networking, chemistry,

business, etc.– Modeling with discrete mathematics is an

extremely important problem-solving skill

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Course Outline• Sets and Propositions • Computability and Formal

Languages • Permutations, Combinations, and

Discrete Probability • Relations and Functions • Graphs and Planar Graphs • Trees and Cut-Sets • Finite State Machines

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Course Outline (Cont.)• Analysis of Algorithms • Discrete Numeric Functions and

Generating Functions • Recurrence Relations and

Recursive Algorithms • Groups and Rings • Boolean Algebras

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Grading• Homework: 0%

– 作業會勾選但不用交• Quiz: 20%

– 每週小考一次 , 時間為當週第一次上課 , 每次約考 10分鐘

• Midterm I: 25%• Midterm II: 25%• Final: 30%