Week 01 Tutorial Sample Answers
Answered in tute.
Answered in tute.
Yes, definitely - that's what the forum is for.
Ask anonymously if you are shy - but very likely other students want the same questions answered.
Yes - useful information about running of DPST1091 will appear in the course forum - e.g. clarification of assignment specifications.
If you are on top of the course materials, you should try answering forum questions.
This will improve your communication skills and often explaining a topic improves your understanding of it too.
How do you make a peanut-butter sandwich?
How could you break that process into steps?
How could you break it down clearly enough that a computer could understand it?
Maybe your tutor could do a live demonstration of following your exact instructions...
Computers are very literal, and you need to tell them *exactly* what to do, without assuming they know what anything means.
For example: "take the peanut butter, and put it on the bread" could mean "pick up the jar of peanut butter and put it on top of the bag of bread".
You need to be very explicit about every step, eg:
- Take a jar of peanut butter.
- Remove the lid from the jar by unscrewing it, and place it on the table next to you.
- Carefully open the bag of bread, without damaging the bread inside, and remove two slices of bread.
- Place the bread on the table next to you, lying flat.
- Take a butterknife, hold it by the handle, and put it into the jar of peanut butter.
- Carefully move the knife through the peanut butter to scoop up approximately a metric teaspoon of peanut butter, and then carefully spread it over one face of the bread, ensuring that the peanut butter is spread evenly and that you don't tear the bread.
What is an operating system?
What operating systems do your classmates run? The tute room? The CSE lab computers?
What are the differences between each of the various operating systems? What differences are there in their interfaces, and how do you interact with them?
What are some different ways in which you can interact with a computer?
What are the differences between graphical user interfaces and the command line? When might one be better than the other?
An operating system (OS) is a series of computer programs (software) that runs on your computer.
It's main function is to manage the running of the computer (keeping things like your mouse and keyboard accessible and keeping hardware drivers up to date) as well as providing an interface for programs to run.
For us in DPST1091, we'll be accessing some of the capability of the operating system when we ask our computer to run our programs.
Common operating systems are Microsoft Windows, Apple OSX and many versions of UNIX/Linux.
In terms of interaction, most operating systems can either use a GUI (Graphical User Interface) which allows us to interact mostly with a mouse/touchpad and visual elements. Most OSes also provide a command line terminal, which allows access purely via text.
A GUI is usually much more user friendly, especially when the user doesn't have much familiarity with computers.
A command line can, for expert users, be much more efficient than a GUI.
// Basic Hello World program
// Marc Chee, September 2020
#include <stdio.h>
int main (void) {
printf("Hello World\n");
return 0;
}
- the
\n - Comments: What should go in a comment? What makes a good comment? How do comments improve program style?
- Indenting and whitespace: What is indented in the sample program? Suggest why.
It outputs a newline at the end of the line, following the character sequence I love DPST1091, starting the next line of output at the beginning of a new line on the terminal window. It is known as the newline escape sequence.
The comment in the example, is a header comment. You should make sure you have a header comment with your name, date and the purpose of your program at the top of every program you write. Comments can also be added throughout your code to make it easier for a human to understand your program.
The code inside the main function block- in between the braces { and } is indented. This is to help humans understand that indented code is inside a set of brackets.
White space is required between C language keywords. For instance you can't have intmain without any intermediate space. Statements are placed on separate lines. Additional blanks lines can be inserted to enhance readability (ie. between printf and return). The closing brace } in this example is aligned beneath the type declaration (int) for the main function, to clearly denote the end of the function block.
face0.c, that behaves as follows:
./face0 ~ ~ 0 0 o -
Sample solution for face0.c:
#include <stdio.h>
int main(void) {
printf("~ ~\n");
printf("0 0\n");
printf(" o\n");
printf(" -\n");
return 0;
}
How would you compile this program?
dcc -o face face.c
How could we modify it to make a program, face1.c, look
like this instead?
./face1 ~ ~ 0 0 o \_/
Sample solution for face1.c
#include <stdio.h>
int main(void) {
printf("~ ~\n");
printf("0 0\n");
printf(" o\n");
printf(" \\_/\n");
return 0;
}
Once you are in your lab, one student from your pair should log into the lab computer.
To log in, you use your zID (which looks something like
z1234567) and your zPass (which is used to log into all other
university online services).
The CSE labs use the Linux operating system (not Windows or OSX or ...).
When you log in, by default, you'll be using the xfce4 window manager, and you'll see a linux desktop.
If you are asked to select a panel click on use default settings.
Along with menus that you can see, such as the Applications Menu in the top left corner, it also has a simple menu you can access by right-clicking anywhere on the desktop.
Have a look around and see if you can work out how to open a web browser.