Find Max Heart Rate Difference

Problem Overview

• Task: Determine the maximum difference between the highest and lowest heart rates recorded within the same activity level over one period.
• Input/Output: Given N consecutive measurements with heartRate[K] and activityLevel[K] in {"Low","Normal","High"}; return a single maximum difference value; constraints not specified.
• Context: Health monitoring device analysis of heart rate by activity level in a real-world tracking scenario.
• Source: Google interviews coding interview problem, commonly used as an interview question.