Card Packets

Problem Overview

• Find the minimum extra cards so all types can be evenly split into the same number of packets (packets > 1).
• Input: cardTypes[n] (counts per type); Output: integer minimum additions; Constraints: 1 ≤ n ≤ 1e5, 1 ≤ cardTypes[i] ≤ 500.
• Real-world domain: e-commerce sports cards, ensuring equal type distribution per packet.
• From Ibm interviews; a classic coding interview problem and interview question.