Max Shared Categories

Problem Overview

• Determine the highest number of common interests any pair of users shares, defined as the greatest integer that divides both users’ counts in this problem.
• Input: array favoriteCategories of length n (2–10^4) with values 1–10^4; Output: an int representing that maximum shared value.
• Context: Analyze TikTok users’ favorite content categories to assess shared interests across the network.
• Source: From TikTok interviews; a classic coding interview problem and interview question.