CS208 Introduction to Computer Systems
Monday, 5 January 2026

+ Hi! 😀
- Welcome back
- Jeff Ondich; call me Jeff; Olin 301A; jondich

+ Today
- Minimal class logistics (more to come on Wednesday)
- integer bases: binary, octal, decimal, and hexadecimal
- using JupyterHub and mantis.mathcs.carleton.edu
- quick look at Thursday's programming assignment
- what to do with a sample program
- some C sample programs: hello.c

+ Meet the prefect

+ Website
- [ASSIGNMENT], [READ], etc.
- Class notes and "slides"
- Class info
- Samples!

+ Integer bases
- base ten (decimal): 173
- base two (binary): 
- base sixteen (hexadecimal): 
- base eight (octal): 

- things you must be able to do, and soon
    - [on quiz] translate binary to decimal (easy but tedious)
    - [not on quiz] translate hexadecimal to decimal (easy but tedious)
    - [on quiz] translate binary to hexadecimal (easy)
    - [on quiz] translate hexadecimal to binary (easy)

- things it's good to be able to do
    - translate decimal to binary (what a pain)
    - use a calculator or python to do all these conversions

python3 -c 'print(bin(173))'
python3 -c 'print(hex(173))'

+ Quiz Wednesday, first 5 minutes of class
- binary to decimal
- binary <--> hexadecimal
- so, let's practice right now
    - ...

+ JupyterHub & mantis.mathcs.carleton.edu

+ Thursday's assignment
- let's read it
- using JupyterHub and mantis to get started

+ hello.c
- go to the samples page in a browser
- connect to mantis
- create hello.c and copy the code over
- gcc -Wall -Werror -g -o hello hello.c
- ./hello

+ more samples
- what should you do with a sample?
    - ...

+ Coming soon
- Thursday programming assignment
- Sunday programming assignment
- Quiz on Wednesday
- Bitwise operators: &, |, ^, ~, <<, >>
- Lots more C and Unix
- Data representation: integers, characters, real numbers, strings