Recursion for Interviews: Think Before You Code
A mental model for solving recursion interview problems without tracing every call. Introduces the 'leap of faith' — trust the recursive call to solve the smaller problem, then define only the base case, the reduction step, and the combine step. Applies the three-question framework to five real interview problems in Python: reversing a linked list, validating a BST with min/max bounds, generating subsets by include/exclude, counting climbing-stairs paths (with memoization), and generating balanced parentheses with backtracking. Covers the recursion-to-DP pipeline, Python's recursion limit, and the follow-up questions interviewers actually ask.