Stack Simulation / Parsing · Expression parsing
Evaluate Reverse Polish Notation
LeetCode 150 · Module: Stack, Queue & Monotonic
The scenario
you only care about the most recent unresolved item or the strongest candidate still standing, so old state has to be removed in the right order.
What you'll learn
- How to recognize the Stack Simulation / Parsing pattern from the problem statement.
- The BASIC Framework breakdown for this problem.
- A clean, interview-ready Python solution with time/space analysis.
Full video, code, and the workspace are part of PatternMastery Pro — 500 problems for one $9.99 payment.