Section checkpoint

Warmup (Code Confidence)

9 questions drawn from the 3 chapters in this section. If most land on the first try, you are ready for the next section. If not, the explanation after each answer says which idea to revisit.

Checkpoint

9 questions · first-try answers earn the most XP

1. Two nested loops each running over n elements give what complexity?

2. What is the time complexity of sorting with a comparison sort such as merge sort?

3. Why does the chapter say a complexity answer should always include space?

4. Why does the palindrome check lowercase and strip non-alphanumerics first?

5. What does "move zeroes" typically mean in the stable-partition sense?

6. Why does the chapter recommend writing the O(n²) version of two-sum first?

7. What does a stack overflow in a recursive function usually indicate?

8. The chapter says to trace one level of recursion and trust the rest. Why?

9. What is the key structural difference between factorial and naive Fibonacci?

What this checkpoint covers

Next section: Core Patterns