Betriebssysteme KU IAIK Graz University of Technology October 6, 2014 Betriebssysteme KU, IAIK October 6, 2014

Transcription

1 Betriebssysteme KU IAIK Graz University of Technology 1

2 1. Organizational Details 2. Rules 3. SWEB 4. Assignment 1 2

3 1. Organizational Details 2. Rules 3. SWEB 4. Assignment 1 3

4 Course Team Aleksander Colovic (Do 16-18) Richard Fellner (Mi 16-18) Thomas Fischer (Mo 13-15) Daniel Gruß (Tue 17-19) Peter Lipp Johanna Rock (Tue 15-17) Michael Schwarz (Mi 14-16) Matthias Seidl (Do 14-16) 4

5 Teaching assistants Will help you with all problems Tutorial units Design discussions Question hours Review meetings (Abgabegespräche) 5

6 Channels Lectures and Tutorials Wiki: 6

7 Channels Lectures and Tutorials Wiki: Newsgroup Organizational: tu-graz.lv.bs SWEB specific: tu-graz.lv.bs.sweb 6

8 Channels Lectures and Tutorials Wiki: Newsgroup Organizational: tu-graz.lv.bs SWEB specific: tu-graz.lv.bs.sweb IRC: irc://irc.at.euirc.net/bs 6

9 Channels Lectures and Tutorials Wiki: Newsgroup Organizational: tu-graz.lv.bs SWEB specific: tu-graz.lv.bs.sweb IRC: irc://irc.at.euirc.net/bs Consultation hour: send us an 6

10 Timeline Assignment Obligatory SWEB tutorials :00 Live programming tutorial (i12) 7

11 Timeline Assignment Obligatory SWEB tutorials :00 Live programming tutorial (i12) Tutorials on A :00 Architecture independency tutorial (i12) 7

12 Timeline Assignment Obligatory SWEB tutorials :00 Live programming tutorial (i12) Tutorials on A :00 Architecture independency tutorial (i12) Design discussions A :00 Deadline design document A1 7

13 Timeline Assignment Obligatory SWEB tutorials :00 Live programming tutorial (i12) Tutorials on A :00 Architecture independency tutorial (i12) Design discussions A :00 Deadline design document A Question hours A :00 Deadline implementation A Review Meetings A1 7

14 Timeline Assignment Tutorials on A :00 Tutorial on OS security features (i12) :00 Tutorial on driver development (i1) 8

15 Timeline Assignment Tutorials on A :00 Tutorial on OS security features (i12) :00 Tutorial on driver development (i1) Design discussions A :00 Deadline design document A2 8

16 Timeline Assignment Tutorials on A :00 Tutorial on OS security features (i12) :00 Tutorial on driver development (i1) Design discussions A :00 Deadline design document A Question hours A :00 Deadline implementation A2 8

17 What we expect from you Knowledge from earlier lectures Rechnerorganisation,... 9

18 What we expect from you Knowledge from earlier lectures Rechnerorganisation,... Reasonable C/C++ experience Experience with Linux 9

19 What we expect from you Knowledge from earlier lectures Rechnerorganisation,... Reasonable C/C++ experience Experience with Linux Team work Time management 9

20 How much effort is it? Depends significantly on your knowledge and experience... 10

21 How much effort is it? Depends significantly on your knowledge and experience and on your team members. 10

22 How much effort is it? Depends significantly on your knowledge and experience and on your team members. KU: 3 ECTS, VO: 3 ECTS Strong synergy between lecture and practicals! 10

23 From Duke university Note to students While we have made an effort to simplify these projects for you, most Duke students find these projects sufficiently difficult to dominate their lives during the one-semester course. 11

24 From Duke university Note to students While we have made an effort to simplify these projects for you, most Duke students find these projects sufficiently difficult to dominate their lives during the one-semester course. A common misconception from earlier semesters is that we are sadistic individuals who enjoy seeing students suffer. 11

25 From Duke university Note to students While we have made an effort to simplify these projects for you, most Duke students find these projects sufficiently difficult to dominate their lives during the one-semester course. A common misconception from earlier semesters is that we are sadistic individuals who enjoy seeing students suffer. Actually, this is not the case. We enjoy seeing students who are proud of what they have accomplished and excited by the power that flows from a relatively small set of simple abstractions in an operating system, even a toy one like Nachos. 11

26 From our evaluations Selten so viel gelernt in einer LV auf der TU Graz. Tutoren sind super und helfen bei jedem Problem zu fast jeder Tages- und Nachtzeit gerne weiter. 12

27 From our evaluations Selten so viel gelernt in einer LV auf der TU Graz. Tutoren sind super und helfen bei jedem Problem zu fast jeder Tages- und Nachtzeit gerne weiter. Die Zeit für die Übungen ist ausreichend. Wird leider trotzdem unterschätzt. Themen. Aufgabenaufteilung. Bonustasks 12

28 From our evaluations Selten so viel gelernt in einer LV auf der TU Graz. Tutoren sind super und helfen bei jedem Problem zu fast jeder Tages- und Nachtzeit gerne weiter. Die Zeit für die Übungen ist ausreichend. Wird leider trotzdem unterschätzt. Themen. Aufgabenaufteilung. Bonustasks Mich hat wirklich beeindruckt wie zutreffend der am Anfang präsentierte Spruch We will not lower the bar, but we will do what we can to help you over it. ist. Die Betreuung und Unterstützung (Tutorien, Fragestunden) ist wirlich hervorragend! 12

29 From our evaluations Selten so viel gelernt in einer LV auf der TU Graz. Tutoren sind super und helfen bei jedem Problem zu fast jeder Tages- und Nachtzeit gerne weiter. Die Zeit für die Übungen ist ausreichend. Wird leider trotzdem unterschätzt. Themen. Aufgabenaufteilung. Bonustasks Mich hat wirklich beeindruckt wie zutreffend der am Anfang präsentierte Spruch We will not lower the bar, but we will do what we can to help you over it. ist. Die Betreuung und Unterstützung (Tutorien, Fragestunden) ist wirlich hervorragend! beste lv dieses semesters, wenn nicht sogar unter allen lven im bachelor 12

30 From our evaluations Man muss zwar viel dafür tun aber der Lernerfolg ist ein Wahnsinn!!! 13

31 From our evaluations Man muss zwar viel dafür tun aber der Lernerfolg ist ein Wahnsinn!!! Beste Übung im Studium bis jetzt, würde sie gerne noch einmal machen ;) 13

32 From our evaluations Man muss zwar viel dafür tun aber der Lernerfolg ist ein Wahnsinn!!! Beste Übung im Studium bis jetzt, würde sie gerne noch einmal machen ;) Ich mochte die KU früher nie. Nachdem ich sie jetzt geschafft habe und mich wirklich damit beschäftigt habe bin ich zufrieden damit! Passt schon :) 13

33 From our evaluations Man muss zwar viel dafür tun aber der Lernerfolg ist ein Wahnsinn!!! Beste Übung im Studium bis jetzt, würde sie gerne noch einmal machen ;) Ich mochte die KU früher nie. Nachdem ich sie jetzt geschafft habe und mich wirklich damit beschäftigt habe bin ich zufrieden damit! Passt schon :) Man merkt immer früher, dass man zu spät angefangen hat... 13

34 From our evaluations Man muss zwar viel dafür tun aber der Lernerfolg ist ein Wahnsinn!!! Beste Übung im Studium bis jetzt, würde sie gerne noch einmal machen ;) Ich mochte die KU früher nie. Nachdem ich sie jetzt geschafft habe und mich wirklich damit beschäftigt habe bin ich zufrieden damit! Passt schon :) Man merkt immer früher, dass man zu spät angefangen hat... Hatte vor Semesterbeginn Angst die Übung negativ abzuschließen, aber mit einer guten Gruppe, und der Hilfe der Tutoren ist sie gut machbar :) 13

35 From our evaluations Man muss zwar viel dafür tun aber der Lernerfolg ist ein Wahnsinn!!! Beste Übung im Studium bis jetzt, würde sie gerne noch einmal machen ;) Ich mochte die KU früher nie. Nachdem ich sie jetzt geschafft habe und mich wirklich damit beschäftigt habe bin ich zufrieden damit! Passt schon :) Man merkt immer früher, dass man zu spät angefangen hat... Hatte vor Semesterbeginn Angst die Übung negativ abzuschließen, aber mit einer guten Gruppe, und der Hilfe der Tutoren ist sie gut machbar :) what does the fork() say? pagefault, pagefault... 13

36 Feedback We try to improve our support constantly Feedback, Evaluations We will not lower the bar, but we will do what we can to help you over it. 14

37 Typical problems Bad time management Problems with working in a team No C/C++ experience 15

38 1. Organizational Details 2. Rules 3. SWEB 4. Assignment 1 16

39 Rule #1 All participants must read the assignments, the rules, newsgroup entries and other important information published by the teaching assistants or the lecturers. 17

40 Rule #1 All participants must read the assignments, the rules, newsgroup entries and other important information published by the teaching assistants or the lecturers. Ignorance is no excuse in law. An overfull mailbox is not either. 17

41 Work diary You will make sketches, notes, write down ideas, etc. during this term Will be considered in case of suspected plagiarism 18

42 Design discussions Take place before the design document deadlines You are expected bring a sketch/summary of your design Prepare to defend your ideas 19

43 Design discussions Take place before the design document deadlines You are expected bring a sketch/summary of your design Prepare to defend your ideas Will be a discussion with the other teams and one or more teaching assistants Improve your design documents 19

44 Design document Your reference document while implementing First two pages: executive summary (mandatory) Teaching assistants may only read the first two pages 20

45 Design document Brief problem description How do you solve the task? Corner cases 21

46 Design document examples Bad: We implement pthread_create which creates new threads... 22

47 Design document examples Bad: We implement pthread_create which creates new threads... Still bad: For thread creation a process has a method Process::createThread(...)... 22

48 Design document examples Bad: We implement pthread_create which creates new threads... Still bad: For thread creation a process has a method Process::createThread(...)... Better: On thread creation the thread copies the thread register values from... 22

49 Design document examples Bad: We implement pthread_create which creates new threads... Still bad: For thread creation a process has a method Process::createThread(...)... Better: On thread creation the thread copies the thread register values from... Good: When a thread is destroyed it checks whether it was the last thread. If so, the thread destroys the process and... 22

50 Git is mandatory Some years ago most students complained, because using git is mandatory Better today: many of you know git already 23

51 Git is mandatory Some years ago most students complained, because using git is mandatory Better today: many of you know git already You have to: push regularly into the provided repository use your real name and address for commits 23

52 Git is mandatory Some years ago most students complained, because using git is mandatory Better today: many of you know git already You have to: push regularly into the provided repository use your real name and address for commits Only one push/commit/other abnormal behaviours : -30% 23

53 POSIX Existing syscall wrapper functions are POSIX-compatible 24

54 POSIX Existing syscall wrapper functions are POSIX-compatible Do not change them! We have automated tests using the POSIX interface 24

55 POSIX Existing syscall wrapper functions are POSIX-compatible Do not change them! We have automated tests using the POSIX interface If you implement new functions, try to make them POSIX-compatible At least the function signature 24

56 Participation Every team member has to participate Making coffee, fetching pizza, etc. 25

57 Participation Every team member has to participate Making coffee, fetching pizza, etc. is not enough 25

58 Participation Every team member has to participate Making coffee, fetching pizza, etc. is not enough We expect all members to understand all parts of the design 25

59 Participation Every team member has to participate Making coffee, fetching pizza, etc. is not enough We expect all members to understand all parts of the design We expect every member to be able to read, explain and change their own implementation, even if it s the code of another team member 25

60 Participation Every team member has to participate Making coffee, fetching pizza, etc. is not enough We expect all members to understand all parts of the design We expect every member to be able to read, explain and change their own implementation, even if it s the code of another team member Otherwise: 0 points 25

61 Testing Goal: a stable and fault tolerant operating system How? 26

62 Testing Goal: a stable and fault tolerant operating system How? By writing test programs 26

63 Testing Goal: a stable and fault tolerant operating system How? By writing test programs Think of test cases when crafting your design Think of basic test scenarios as well as corner cases 26

64 Testing Writing numerous test programs is unavoidable 27

65 Testing Writing numerous test programs is unavoidable Test programs are supposed to show whether your implementation works according to the assignment You will get points for the test programs 27

66 Testing Writing numerous test programs is unavoidable Test programs are supposed to show whether your implementation works according to the assignment You will get points for the test programs We have our own secret test programs 27

67 Testing Bad: Not knowing of a problem until the review meeting 28

68 Testing Bad: Not knowing of a problem until the review meeting Better: Knowing of a problem but not solving it (probably because time ran out) 28

69 Testing Bad: Not knowing of a problem until the review meeting Better: Knowing of a problem but not solving it (probably because time ran out) Best: Knowing of a problem sufficiently before the deadline and solving it (maybe with the help of a teaching assistant) 28

70 README You have to add a README file to your submission 29

71 README You have to add a README file to your submission Contains information on how to use your implementation Differences between design an implementation are described Additional features are listed and described 29

72 Submissions Tag the commit you want to submit: git tag SubmissionD1 [commit_hash] 30

73 Submissions Tag the commit you want to submit: git tag SubmissionD1 [commit_hash] Push to repository: git push / git push --tags 30

74 Submissions Tag the commit you want to submit: git tag SubmissionD1 [commit_hash] Push to repository: git push / git push --tags Read the commit ID: git show SubmissionD1 commit 196bc4a704f37d7f969d27a258b513693e3b30f4 Author: Peter Lipp <peter.lipp@iaik.tugraz.at> 30

75 Submissions Mail to and to your teaching assistant Subject: Submission Team <teamid> <tag> <commitid> Example: Submission Team G01 SubmissionD1 196bc4a

76 Submissions Mail to and to your teaching assistant Subject: Submission Team <teamid> <tag> <commitid> Example: Submission Team G01 SubmissionD1 196bc4a7... Design document A1 Tag: SubmissionD1 Implementation A1 Tag: SubmissionI1 Wrong format/tag/... less points 31

77 Late Submissions If you submit after the deadline (always 18:00) you get points deduced 0-24 hours: 30% hours: 40% hours: 60% You must inform your teaching assistant in advance! 32

78 Assessment A1 Reference (=100%) Design document: 5 points Task 1: 20 points Task 2: 10 points Elective tasks*: 15 points (or more) 33

79 Assessment A1 Reference (=100%) Design document: 5 points Task 1: 20 points Task 2: 10 points Elective tasks*: 15 points (or more) Minimum Design document 1 point Mandatory tasks: 15 points And in total: 25 points (=50%) (*) See the list of elective tasks in the Swebwiki! 33

80 Assessment A2 Reference (=100%) Design document: 5 points Mandatory tasks: 40 points Elective tasks*: 5 points (or more) 34

81 Assessment A2 Reference (=100%) Design document: 5 points Mandatory tasks: 40 points Elective tasks*: 5 points (or more) Minimum Design document 1 point Mandatory tasks: 15 points And in total: 25 points (=50%) (*) See the list of elective tasks in the Swebwiki! 34

82 Plagiarism Discussions with other teams are appreciated But: no Collaboration! 35

83 Plagiarism Discussions with other teams are appreciated But: no Collaboration! We check for plagiarism Similarities teams are questioned 35

84 Plagiarism Discussions with other teams are appreciated But: no Collaboration! We check for plagiarism Similarities teams are questioned Consequence: 0 points 35

85 Plagiarism Do not provide your source code to other teams 36

86 Plagiarism Do not provide your source code to other teams Make sure your source code is protected against unintended access from others 36

87 Plagiarism Do not provide your source code to other teams Make sure your source code is protected against unintended access from others Do not use source code from previous years Code from another team plagiarism 36

88 Plagiarism Do not provide your source code to other teams Make sure your source code is protected against unintended access from others Do not use source code from previous years Code from another team plagiarism Your own code (not exactly the same team) not allowed 36

89 Plagiarism Do not provide your source code to other teams Make sure your source code is protected against unintended access from others Do not use source code from previous years Code from another team plagiarism Your own code (not exactly the same team) not allowed Your own code (exactly the same team) allowed, probably not the best idea ;) 36

90 Review meetings (Abgabegespräche) As a group You explain what you implemented and how you tested it Together with the teaching assistant you determine the points of your group 37

91 Review meetings (Abgabegespräche) As a group You explain what you implemented and how you tested it Together with the teaching assistant you determine the points of your group As a group member You are able to read, explain and change the code You can implement small new features or extend existing ones Otherwise you will get less points 37

92 Assessment of the practicals Minimum requirements A1: 25 of 50 points A2: 25 of 50 points 38

93 Assessment of the practicals Minimum requirements A1: 25 of 50 points A2: 25 of 50 points Limits A1: max. 60 points Unlimited if A2 40 points A2: unlimited points 38

94 Assessment: Modes You can choose a mode: VO/KU mode: seperate marks for lecture (VO) and practicals (KU) VU mode: 39

95 Assessment: Modes You can choose a mode: VO/KU mode: seperate marks for lecture (VO) and practicals (KU) VU mode: Default mode in summer term Results in practicals and written exams will be unified into one mark Different weights applied ( next slide) 39

96 Assessment: Getting a grade (VU mode) VU mode two written exams: 20% each the practicals: 60% 40

97 Assessment: Getting a grade (VU mode) To pass the class, you have to acquire overall at least 55% 41

98 Assessment: Getting a grade (VU mode) To pass the class, you have to acquire overall at least 55% at least 50% of the possible points in one written exam and at least 33% in the other 41

99 Assessment: Getting a grade (VU mode) To pass the class, you have to acquire overall at least 55% at least 50% of the possible points in one written exam and at least 33% in the other at least 50% of the possible points in the practicals 41

100 Assessment: Getting a grade (both modes) Marks genügend: befriedigend: gut:79-89 sehr gut:

101 Questions so far? 43

102 1. Organizational Details 2. Rules 3. SWEB 4. Assignment 1 44

103 History and the others VU Amsterdam: Minix (1987), Minix3 (2005) 45

104 History and the others VU Amsterdam: Minix (1987), Minix3 (2005) Berkeley: Nachos (1992) 45

105 History and the others VU Amsterdam: Minix (1987), Minix3 (2005) Berkeley: Nachos (1992) Stanford: Pintos (2004) 45

106 History and the others VU Amsterdam: Minix (1987), Minix3 (2005) Berkeley: Nachos (1992) Stanford: Pintos (2004) Graz Nachos until 2006 Now: SWEB 45

107 History of SWEB BS KU 2004/

108 History of SWEB BS KU 2004/2005 Advanced group of students together with Philip Lawatsch and Bernhard Tittelbach 46

109 History of SWEB BS KU 2004/2005 Advanced group of students together with Philip Lawatsch and Bernhard Tittelbach Many subsequent projects 46

110 History of SWEB BS KU 2004/2005 Advanced group of students together with Philip Lawatsch and Bernhard Tittelbach Many subsequent projects BS KU: since 2007 SWEB only 46

111 Base Line SWEB Minimalistic operating system kernel Runs on x86-32, x86-64, ARM Emulated using qemu ( Demo) 47

112 Base Line SWEB Minimalistic operating system kernel Runs on x86-32, x86-64, ARM Emulated using qemu ( Demo) Important features are missing Your task: Make your SWEB a beautiful, feature-rich kernel 47

113 What is possible in SWEB Mouse driver 48

114 What is possible in SWEB Mouse driver Window manager 48

115 What is possible in SWEB Mouse driver Window manager Network driver 48

116 What is possible in SWEB Mouse driver Window manager Network driver Soundblaster driver 48

117 What is possible in SWEB Mouse driver Window manager Network driver Soundblaster driver Gameboy emulator 48

118 What is possible in SWEB Mouse driver Window manager Network driver Soundblaster driver Gameboy emulator 3D game engine ( Demo) 48

119 First steps Try out the tutorials on Set up development environment Implement your first syscall... 49

120 First steps Try out the tutorials on Set up development environment Implement your first syscall... Start your work diary 49

121 First steps Try out the tutorials on Set up development environment Implement your first syscall... Start your work diary Get acquainted with the source code: Try out implementing things in SWEB 49

122 First steps Try out the tutorials on Set up development environment Implement your first syscall... Start your work diary Get acquainted with the source code: Try out implementing things in SWEB Visit tutorials and lecture 49

123 Road to success Start with the practicals NOW! 50

124 Road to success Start with the practicals NOW! Use the synergy between lecture and practicals 50

125 Road to success Start with the practicals NOW! Use the synergy between lecture and practicals Try out the VU mode 50

126 Bugs and Patches Report Bugs and submit patches to 51

127 Bugs and Patches Report Bugs and submit patches to SWEB recently ported to x86-64 and ARM architecture Potentially new bugs Possible improvements Some features incomplete 51

128 1. Organizational Details 2. Rules 3. SWEB 4. Assignment 1 52

129 Task 1: Multithreading Base line SWEB: a user process is a (kernel) thread 53

130 Task 1: Multithreading Base line SWEB: a user process is a (kernel) thread We want: multiple threads per user process 53

131 Task 1: Multithreading Base line SWEB: a user process is a (kernel) thread We want: multiple threads per user process What do we have to change? 53

132 Task 1: Multithreading Each thread has its own instances of some resources id, stack, registers, status,... 54

133 Task 1: Multithreading Each thread has its own instances of some resources id, stack, registers, status,... Other resources are shared among all threads memory, files,... 54

134 Task 1: Multithreading How to use multithreading? 55

135 Task 1: Multithreading How to use multithreading? Syscalls! Which ones? 55

136 Task 1: Multithreading How to use multithreading? Syscalls! Which ones? You decide - but function names and arguments have to be POSIX-compatible! 55

137 Task 1: Multithreading How to use multithreading? Syscalls! Which ones? You decide - but function names and arguments have to be POSIX-compatible! Minimum requirements: pthread_create pthread_exit pthread_cancel pthread_join 55

138 Syscalls (system calls) Operating system is written by people who know what they do 56

139 Syscalls (system calls) Operating system is written by people who know what they do User programs? 56

140 Syscalls (system calls) Operating system is written by people who know what they do User programs? System calls provide a safe interface 56

141 Syscalls (system calls) Operating system is written by people who know what they do User programs? System calls provide a safe interface Control flow is transmitted to kernel code 56

142 Syscalls (system calls) Operating system is written by people who know what they do User programs? System calls provide a safe interface Control flow is transmitted to kernel code Typical syscalls: fork(), read(), write(), execve(), wait(), exit() 56

143 Syscalls (system calls) Operating system is written by people who know what they do User programs? System calls provide a safe interface Control flow is transmitted to kernel code Typical syscalls: fork(), read(), write(), execve(), wait(), exit() You will step through a syscall in the tutorial this week! 56

144 Task 2: fork fork() creates a new process by duplicating the calling process The new process (=the child), is an exact duplicate of the calling process (=the parent) 57

145 Task 2: fork fork() creates a new process by duplicating the calling process The new process (=the child), is an exact duplicate of the calling process (=the parent) Interesting in combination with multithreading! 57

146 Additional Task: exec Replaces the current process image with a new process image 58

147 Additional Task: exec Replaces the current process image with a new process image exec with arguments more points 58

148 Additional Task: exec Replaces the current process image with a new process image exec with arguments more points fork()/exec() combination often used 58

149 Additional Task: sleep/clock sleep() sets a thread asleep for a given number of seconds 59

150 Additional Task: sleep/clock sleep() sets a thread asleep for a given number of seconds clock returns how much cpu time the current process consumed 59

151 Additional Task: exit exit() terminates the current process 60

152 Additional Task: exit exit() terminates the current process Already implemented, but... 60

153 Additional Task: exit exit() terminates the current process Already implemented, but you will break the current implementation with multithreading 60

154 Additional Task: I/O syscalls I/O syscalls are already implemented, but... 61

155 Additional Task: I/O syscalls I/O syscalls are already implemented, but they use global (not process specific) file descriptors Why is that a problem? 61

156 Additional Task: Synchronization Threads need synchronization 62

157 Additional Task: Synchronization Threads need synchronization Kernel has mutexes and condition variables 62

158 Additional Task: Synchronization Threads need synchronization Kernel has mutexes and condition variables We want: mutexes, condition variables and semaphores, both in kernelspace and userspace 62

159 Additional Task: Synchronization Threads need synchronization Kernel has mutexes and condition variables We want: mutexes, condition variables and semaphores, both in kernelspace and userspace Pure userspace implementation (except for initialization and for going to sleep) 62

160 Additional Task: Synchronization Threads need synchronization Kernel has mutexes and condition variables We want: mutexes, condition variables and semaphores, both in kernelspace and userspace Pure userspace implementation (except for initialization and for going to sleep) Implement test programs (Readers-Writers-Problem, Sleeping Barber, etc.) 62

161 Additional Task: Your own ideas Own ideas are the most fun! 63

162 Additional Task: Your own ideas Own ideas are the most fun! See bs/assignments for suggestions 63

163 Additional Task: Your own ideas Own ideas are the most fun! See bs/assignments for suggestions Please note: Assignment 1 tasks will only be counted in Assignment 1 assessment 63

164 Additional Task: Your own ideas Own ideas are the most fun! See bs/assignments for suggestions Please note: Assignment 1 tasks will only be counted in Assignment 1 assessment Assignment 2 tasks will only be counted in Assignment 2 assessment 63

165 Happy programming! 64