Find Optimal Input

Problem Overview

• Find the optimal microwave keypad input minimizing cost for a given target cooking time.
• Input: targetTime in seconds; Output: integer input value (findOptimalInput).
• Candidate inputs must be within 10% of target; if costs tie, choose the closest time.
• Digit sequences are parsed as minutes:seconds per microwave rules (e.g., 999->9m99s, 81->81s, 1221->12m21s).
• A Google interviews coding interview problem and interview question set in a real-world microwave context.