Introduction

The aim of this assignment is to make sure that you understand and are familiar with the concepts covered in the lectures, including Unix operating system, programming paradigms, the structure of programming languages, and the differences between a macro and a procedure. By the end of the assignment, you should have

• Learned a brief history of programming languages and the characteristics of the languages.
• Gotten started with Unix and GNU GCC the programming environment.

This assignment is related to the outcomes 1-2 and 1-3 listed in the syllabus:

• Students will understand the control structures of functional, logic, and imperative programming languages.
• Students will understand the execution of functional, logic, and imperative programming languages.

Optional Reading (6e): Read chapter 1, chapter 2 (sections 2.1, 2.2, and 2.3), appendix (sections B.1 and B.2), and course notes (slides).

You are encouraged to ask and answer questions on the course Slack. (However, do not share your answers or code.)

Pre-requisite

This homework requires using the GCC compiler installed on ASUs general server. By the time you start this homework, you should have already read the page called M1 & 2: GCC and Visual Studio on Canvas. This page of the homework reiterates some of the ideas of accessing GCC.

To do the C assignments using GNU GCC, you need to have basic Unix knowledge. If you are not familiar with basic Unix commands, you may need to read the Unix Tutorial given on Canvas.

• Run a program such as PuTTY or SSH on your PC or Mac. Configure the terminal program to connect to asu.edu on port 22. Note: if you are running on Linux or a Mac, then you can start an SSH connection to General by opening a terminal window and typing ssh yourasuruteid@general.asu.edu at the prompt.

• Log in to General using your ASUAD
• Do an ls command to see the files in your home directory.
• Do an ls -a command to see all of the files in your home directory, including hidden files.
• Do an ls -l command to produce a long listing of the non-hidden files in your home directory.
• Do an ls -al command to produce a long listing of all of the files in your home directory.

Make a new directory (e.g. MyDir or CSE240) by using the command: mkdir MyDir, use this to store all of your C and C++ programs in a specific directory. You may create subdirectories in this directory.

Enter the directory by using Change Directory command: cd MyDir

To write a GNU GCC program on a Unix server, you can either use a Unix editor, e.g., nano, vim or pico or upload (myFiles) a file into your Unix directory MyDir. The name of a C program should have an extension .c and the name of a C++ program should have an extension .cpp

Programming Exercise

1. Review the lecture slides which discuss Very Simple Programming Languages (VSPL). Next, review VSPL as defined below and identify which sequences are valid.

<letter> ::= a | b | c | d | e

<LETTER> ::= V | W | X | Y | Z

<number> ::= 0 | 1 | 2 | 3 | 4

<letters> ::= <letter> | <letter> <letters>

<LETTERS> ::= <LETTER> | <LETTER> <LETTERS>

<numbers> ::= <number> | <number> <numbers>

<sequence> ::= <letters> <LETTERS> <numbers> | <LETTERS> <letters> <numbers>

Which of the following are valid sequences? You must clearly identify for each of the following sequences, which are valid and which are invalid. Each sequence is worth 1 point. Submit your answer as hw01q1.pdf. [10 points]

1. CSE240
2. ebcXYZ125
3. XYZcde344
4. VWXa10
5. edc135790Z
6. dYaZeWkV
7. Zbad00
8. aZ21
9. XYZabc23
10. Ey701

2. Follow the Textbook Appendix B and the Unix Tutorial PPT given in the homework folder to complete the following tasks on the ASU General server:
   • Create a new directory called CSE240. Use cd CSE240 to enter the new directory. Use pwd command to find the path from the Unix root directory to your current directory.
   • Create three new subdirectories inside CSE240. Name the directories d1, d2, and d3 respectively.
   • Enter the directory d1 and use nano or vim to create a new program called hello.c and enter the following code into the program. You must use your name to replace the name John Doe. Save the file.

Use gcc hello.c -o hello to compile the program. Fix any compilation errors if any.

• Use ls, ls -l, and ls -al respectively to list files in d1 directory. Use command ./hello to execute the compiled code. .

Take screenshots of each command in this question. You may take one screenshot with all commands in it.

• Enter d2 directory and then use one command to copy (not move) the files hello.c and hello from d1 directory into d2 directory. Use ls -al to view all the files in d2.

Take screenshots of each command in this question. You may take one screenshot with all commands in it.

• In d2 directory, use chmod 660 hello to change the permission. Use ls -l to view the files. Use command ./hello to execute the compiled code. Take a screenshot of this output. Use chmod command again to make hello an executable, but not readable and not writeable for all users. Use command ./hello to execute the compiled code.

Take a screenshot of this output. [3 points]

• Enter CSE240 directory. Use ls -l to view all the files. Then, use one command to delete d2 directory and all the files in d2 directory. Use ls -l to view all the files.

Take screenshots of each command in this question. You may take one screenshot with all commands in it. [3 points]

Screenshots are needed for questions 2.4 through 2.7. Put all the screenshots along with their question numbers in a word file and convert to pdf. Submit the file as hw01q2.pdf

3. In this question, you will use Unix tools to edit, debug, and execute a small C program. The purpose of the homework is to learn the Unix programming environment. Optionally read textbook Section 2.2.3, the tutorials, and the Unix tutorial in text Appendix B.2.
   • Use a text editor to enter the program on textbook page 47 (the code is given here for your convenience). Use GNU GCC to compile, debug (find and fix any syntax errors), and execute the program and fix any semantic errors, for example, by adding break statements in the required places and by fixing incorrect characters copied into the programming environment, if any, and by type-changing to print a floating point number. The code is supposed to perform one math operation in each switch-case. The ch variable is assigned a new math operator before each switch-

case. Submit the corrected program as hw01q3.c

4. You are given a file named hw01q4.c. All instructions are given in the form of comments in the file. You should correct the errors and identify which error type they are. Please read all instructions carefully, then complete and submit the updated file. [20 points]