Consider a problem in the PDF: "Write a function to remove duplicate items from a list." That is a toy problem. That is:
Problem: Two-sum — find indices of two numbers that add to target. Approach: Single-pass hash map storing complement → index. Complexity: O(n) time, O(n) space. Key edge cases: duplicate numbers, same index reuse. Learn To Code By Solving Problems Pdf
The methodology flips the script. It starts with a question, not an answer. Consider a problem in the PDF: "Write a