Lesson 027
Introduction to Lists
Dynamic Arrays That Grow & Shrink
1:00How dynamic arrays (lists) grow and shrink on demand, why append is amortized O(1), and when to prefer a list over a fixed array.
By the end, you can
- Explain why a list can grow and shrink while a fixed array cannot.
- Describe what happens internally (allocate, copy, headroom) when a list resizes.
- Distinguish **length** from **capacity** and state what happens to each when items are removed.
- Explain **amortized O(1)** append and why doubling is the key to making it work.
- State the time complexity of access, append, insert, and search on a list.
- Identify and fix the off-by-one indexing pitfall and the mutate-while-iterating pitfall.
- Recognize the list equivalent in Python, JavaScript, Java, and C++.
- Decide when a list is the right data structure versus when a fixed array suffices.
Up next in Linear Data Structures
