4 lessons
What Are Data Structures and Algorithms
Why the way you store data decides how fast your program runs, and how to start thinking about both.
Time Complexity
Big O, Big Omega, Big Theta and the little-o cousins — every notation used to describe how an algorithm grows, with practice questions along the way.
Space Complexity
Memory has a cost too, and the recursion stack counts even when you never allocate anything.
Recursion Fundamentals
Define a base case, shrink the input, and trust the recursive call to do the rest.