## Practice Problems

Everything on this page is optional content. To learn the course material, focus first on participating in lecture and recitation, completing the exercises, and completing the assignments. You can then use these practice materials if you'd like additional practice.

#### OLI Problems

We have implemented practice problems with answer-checking and correct solutions in OLI, the Online Learning Initiative. To sign up for the OLI course, go to

https://oli.cmu.edu/students/, click 'Register with Course Key', log in through your CMU account, then enter the course key:

**15-110-S23**
There are currently OLI modules on:

- Introduction to Python
- Strings
- For Loops
- Lists
- Recursion
- Dictionaries
- Big-O Runtime
- Graphs
- Simulation

#### TA-Generated Problems

Past course TAs have generated practice problems for each lecture of the course. You can find PDFs for each lecture's problems below.

**Unit 1**
**Unit 2**
**Unit 3**
**Unit 4**
**Unit 5**

#### External Problems

Here are some helpful websites that host Python practice problems! Note that the problems you find on these websites may not always align with the content being taught in class.