Get Minimum Removal

Problem Overview

• Determine the minimum number of products to remove so the catalogue has at most k distinct categories.
• Input: n, an array catalogue of length n with category IDs, and k; Output: an integer for the minimum removals.
• Constraints: 1 ≤ n, k, catalogue[i] ≤ 1e5.
• Real-world context: cleaning an Amazon product catalogue; a common coding interview problem.
• Company: From Amazon interviews; classic interview question.