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This document provides an overview of the BBM 201 Data Structures course. It discusses that the course will help students understand basic data structures like matrices, stacks, queues, and linked lists. It will include programming assignments to provide hands-on experience. Students must have basic programming skills. References for the course are provided. The course website will be updated regularly and used for communication. Office hours and help resources are available. Exams, quizzes, and assignments will be used for grading. Programming assignments will involve solving problems and working individually. Cheating policies are outlined. An introduction to basic data structure concepts is provided, including choosing appropriate data structures based on tasks.

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BBM 201 DATA STRUCTURES Lecture 1: Basic concepts for data structures
About the course • This course will help students understand the basic data structures such as matrices, stacks, queues, linked lists, etc. • BBM 203 Programming Laboratory: The students will gain hand-on experience via a set of programming assignments supplied as complementary. • Requirements: You must know basic programming (i.e. BBM101).
References • Data Structures and Algorithm Analysis in C++. 4th Edition. Mark Allen Weiss, Pearson, 2014 • Fundamentals of Data Structures in C++. Ellis Horowitz, Sartaj Sahni, and Susan Anderson-Freed, Computer Science Press, 1995. • Data Structures Notes, Mustafa Ege. •
Communication • The course web page will be updated regularly throughout the semester with lecture notes, programming assignments, announcements and important deadlines. http://web.cs.hacettepe.edu.tr/~bbm201
Getting Help • Office hours See the web page for details • BBM 203 Programming Laboratory Course related recitations, practice with example codes, etc. • Communication Announcements and course related discussions through BBM 201: https://piazza.com/hacettepe.edu.tr/fall2021/bbm201 BBM 203: https://piazza.com/hacettepe.edu.tr/fall2021/bbm203
Course Work and Grading • 1 midterm exam (25%) • Quizzes (25%) (5 out of 6) • Final exam (50%)
Course Overview
BBM 203 Programming Laboratory I • Programming assignments (PAs) • Four assignments throughout the semester. • Each assignment has a well-defined goal such as solving a specific problem. • You must work alone on all assignments stated unless otherwise.
BBM 203 Programming Laboratory I
Policies • Work groups • You must work alone on all assignments stated unless otherwise • Submission • Assignments due at 23:59 (no extensions!) • Electronic submissions (no exceptions!) • Lateness penalties • No late submission is accepted
Cheating • What is cheating? • Sharing code: by copying, retyping, looking at, or supplying a file • Coaching: helping your friend to write a programming assignment, line by line • Copying code from previous course or from elsewhere on WWW • What is NOT cheating? • Explaining how to use systems or tools • Helping others with high-level design issues
Cheating • Penalty for cheating: • Suspension from school for 6 months (minimum) • Detection of cheating: • We do check: Our tools for doing this are much better than most cheaters think!
BASIC CONCEPTS FOR DATA STRUCTURES
Lecture 1
Lecture 1
Lecture 1
Lecture 1
Lecture 1
Data Structures→Data StructurING How do we organize information so that we can find, update, add, and delete portions of it efficiently?
Data Structure Example Applications • How does Google quickly find web pages that contain a search term? • What’s the fastest way to broadcast a message to a network of computers? • How can a subsequence of DNA be quickly found within the genome? • How does your operating system track which memory (disk or RAM) is free? • In the game Half-Life, how can the computer determine which parts of the scene are visible?
Suppose You’re Google Maps… • You want to store data about cities (location, elevation, population)… What kind of operations should your data structure(s) support?
Operations to support the following scenario… Finding addresses on map? • Lookup city by name... Mobile user? • Find nearest point to me... Car GPS system? • Calculate shortest-path between cities… • Show cities within a given window… Political revolution? • Insert, delete, rename cities
How will you count user views on YouTube? • Lets write a userViewCount() function int userViewCount (int current_count) { int new_count; new_count =current_count + 1; return new_count; } Will this implementation work all the time?
How will you count user views on YouTube? %99.9 times yes.
How will you count user views on YouTube? http://www.bbc.com/news/world-asia- 30288542 YouTube's counter previously used a 32-bit integer YouTube said the video - its most watched ever - has been viewed more than 2,147,483,647 times. It has now changed the maximum view limit to 9,223,372,036,854,775,808, or more than nine quintillion. http://www.economist.com/blogs/economist- explains/2014/12/economist-explains-6
How bad can it be? • June 4, 1996 • Ariane 5 rocket launched by the European Space Agency • After a decade of development costing $7 Billion (~42 Billion in Turkish Liras, just for comparison Istanbul’s third bridge cost estimates are 4.5 Billion TL) • Exploded just 40 seconds after its lift-off • The destroyed rocket and its cargo were valued at $500 million • Reason?
How bad can it be? • Reason? • Inertial reference system error: specifically a 64 bit floating point number relating to the horizontal velocity of the rocket with respect to the platform was converted to a 16 bit signed integer. • The number was larger than 32,767, the largest integer storable in a 16 bit signed integer, and thus the conversion failed. • $500 Million rocket/cargo • Time and effort
Floating Point Representation
Floating Point Representation
Goals “I will, in fact, claim that the difference between a bad programmer and a good one is whether he considers his code or his data structures more important. Bad programmers worry about the code. Good programmers worry about data structures and their relationships.” Linus Torvalds, 2006 30
Data Structures A data structure is a way to store and organize data in computer, so that it can be used efficiently. Some of the more commonly used data structures include lists, arrays, stacks, queues, heaps, trees, and graphs. Binary Tree
What are data structures? • Data structures are software artifacts that allow data to be stored, organized and accessed. • Ultimately data structures have two core functions: put stuff in and take stuff out.
Why so many? • Space efficiency • Time efficiency: • Store • Search • Retrieve • Remove • Clone etc.
Choosing Data Structures Queue vs Binary Tree ---Which one to use for what task?
Why So Many Data Structures? • Ideal data structure: • “fast”, “elegant”, memory efficient • Generates tensions: • time vs. space • performance vs. elegance • generality vs. simplicity • one operation’s performance vs. another’s The study of data structures is the study of tradeoffs. That’s why we have so many of them!

More Related Content

Lecture 1

  • 1. BBM 201 DATA STRUCTURES Lecture 1: Basic concepts for data structures
  • 2. About the course • This course will help students understand the basic data structures such as matrices, stacks, queues, linked lists, etc. • BBM 203 Programming Laboratory: The students will gain hand-on experience via a set of programming assignments supplied as complementary. • Requirements: You must know basic programming (i.e. BBM101).
  • 3. References • Data Structures and Algorithm Analysis in C++. 4th Edition. Mark Allen Weiss, Pearson, 2014 • Fundamentals of Data Structures in C++. Ellis Horowitz, Sartaj Sahni, and Susan Anderson-Freed, Computer Science Press, 1995. • Data Structures Notes, Mustafa Ege. •
  • 4. Communication • The course web page will be updated regularly throughout the semester with lecture notes, programming assignments, announcements and important deadlines. http://web.cs.hacettepe.edu.tr/~bbm201
  • 5. Getting Help • Office hours See the web page for details • BBM 203 Programming Laboratory Course related recitations, practice with example codes, etc. • Communication Announcements and course related discussions through BBM 201: https://piazza.com/hacettepe.edu.tr/fall2021/bbm201 BBM 203: https://piazza.com/hacettepe.edu.tr/fall2021/bbm203
  • 6. Course Work and Grading • 1 midterm exam (25%) • Quizzes (25%) (5 out of 6) • Final exam (50%)
  • 8. BBM 203 Programming Laboratory I • Programming assignments (PAs) • Four assignments throughout the semester. • Each assignment has a well-defined goal such as solving a specific problem. • You must work alone on all assignments stated unless otherwise.
  • 9. BBM 203 Programming Laboratory I
  • 10. Policies • Work groups • You must work alone on all assignments stated unless otherwise • Submission • Assignments due at 23:59 (no extensions!) • Electronic submissions (no exceptions!) • Lateness penalties • No late submission is accepted
  • 11. Cheating • What is cheating? • Sharing code: by copying, retyping, looking at, or supplying a file • Coaching: helping your friend to write a programming assignment, line by line • Copying code from previous course or from elsewhere on WWW • What is NOT cheating? • Explaining how to use systems or tools • Helping others with high-level design issues
  • 12. Cheating • Penalty for cheating: • Suspension from school for 6 months (minimum) • Detection of cheating: • We do check: Our tools for doing this are much better than most cheaters think!
  • 19. Data Structures→Data StructurING How do we organize information so that we can find, update, add, and delete portions of it efficiently?
  • 20. Data Structure Example Applications • How does Google quickly find web pages that contain a search term? • What’s the fastest way to broadcast a message to a network of computers? • How can a subsequence of DNA be quickly found within the genome? • How does your operating system track which memory (disk or RAM) is free? • In the game Half-Life, how can the computer determine which parts of the scene are visible?
  • 21. Suppose You’re Google Maps… • You want to store data about cities (location, elevation, population)… What kind of operations should your data structure(s) support?
  • 22. Operations to support the following scenario… Finding addresses on map? • Lookup city by name... Mobile user? • Find nearest point to me... Car GPS system? • Calculate shortest-path between cities… • Show cities within a given window… Political revolution? • Insert, delete, rename cities
  • 23. How will you count user views on YouTube? • Lets write a userViewCount() function int userViewCount (int current_count) { int new_count; new_count =current_count + 1; return new_count; } Will this implementation work all the time?
  • 24. How will you count user views on YouTube? %99.9 times yes.
  • 25. How will you count user views on YouTube? http://www.bbc.com/news/world-asia- 30288542 YouTube's counter previously used a 32-bit integer YouTube said the video - its most watched ever - has been viewed more than 2,147,483,647 times. It has now changed the maximum view limit to 9,223,372,036,854,775,808, or more than nine quintillion. http://www.economist.com/blogs/economist- explains/2014/12/economist-explains-6
  • 26. How bad can it be? • June 4, 1996 • Ariane 5 rocket launched by the European Space Agency • After a decade of development costing $7 Billion (~42 Billion in Turkish Liras, just for comparison Istanbul’s third bridge cost estimates are 4.5 Billion TL) • Exploded just 40 seconds after its lift-off • The destroyed rocket and its cargo were valued at $500 million • Reason?
  • 27. How bad can it be? • Reason? • Inertial reference system error: specifically a 64 bit floating point number relating to the horizontal velocity of the rocket with respect to the platform was converted to a 16 bit signed integer. • The number was larger than 32,767, the largest integer storable in a 16 bit signed integer, and thus the conversion failed. • $500 Million rocket/cargo • Time and effort
  • 30. Goals “I will, in fact, claim that the difference between a bad programmer and a good one is whether he considers his code or his data structures more important. Bad programmers worry about the code. Good programmers worry about data structures and their relationships.” Linus Torvalds, 2006 30
  • 31. Data Structures A data structure is a way to store and organize data in computer, so that it can be used efficiently. Some of the more commonly used data structures include lists, arrays, stacks, queues, heaps, trees, and graphs. Binary Tree
  • 32. What are data structures? • Data structures are software artifacts that allow data to be stored, organized and accessed. • Ultimately data structures have two core functions: put stuff in and take stuff out.
  • 33. Why so many? • Space efficiency • Time efficiency: • Store • Search • Retrieve • Remove • Clone etc.
  • 34. Choosing Data Structures Queue vs Binary Tree ---Which one to use for what task?
  • 35. Why So Many Data Structures? • Ideal data structure: • “fast”, “elegant”, memory efficient • Generates tensions: • time vs. space • performance vs. elegance • generality vs. simplicity • one operation’s performance vs. another’s The study of data structures is the study of tradeoffs. That’s why we have so many of them!