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rippling·Software Engineer·Onsite - Coding / Algorithms·Intermediate

Intermediate
Apr 2026Remote

Summary

Virtual onsite at Rippling for a software engineer role. The AI coding round had the Camel Cards problem, which is a puzzle-style question that shows up in competitive programming contexts. Not a typical leetcode grind session.

Questions Asked (1)

Q1

Solve the Camel Cards problem: implement a card hand ranking system where hands are compared by type (five of a kind, full house, etc.) and then by card value order.

Algorithms & Data Structures
Author's notes

This one is pulled straight from Advent of Code so if you've done that before you'd recognize it immediately.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the problem requirements, especially the card order and hand types. Then outline a solution that parses each hand, determines its type, and compares hands by type first, then by card values in order. Finally, discuss implementation details and complexity.

Pro tip: Mention that you can encode each hand as a tuple (hand_type, card_values) and sort using that tuple, which simplifies comparison and avoids custom comparator logic. Also, note that handling the joker variant (if applicable) requires careful adjustment of hand type evaluation.

1. Clarify requirements

Confirm the card order (e.g., 2-9, T, J, Q, K, A) and hand types (five of a kind, four of a kind, full house, etc.). Ask if jokers are involved and how they affect hand types.

2. Design hand representation

Represent each hand as a string of 5 cards. Map each card to a numeric value for easy comparison. Count card frequencies to determine hand type.

3. Determine hand type

Based on frequency counts, assign a numeric rank to each hand type (e.g., five of a kind = 7, four of a kind = 6, etc.). Handle special cases like jokers if needed.

4. Implement comparison

Compare hands by hand type first; if equal, compare card values in order from left to right. Use a tuple (hand_type, card_values) for easy sorting.

5. Analyze complexity

Sorting n hands takes O(n log n) time. Each comparison is O(1) since hands have fixed size. Space complexity is O(n) for storing hands.

Key Points to Mention

  • Card value mapping: assign numeric values to cards according to the given order.
  • Hand type ranking: define an enum or integer ranking for each hand type.
  • Frequency counting: use a hash map or array to count occurrences of each card.
  • Comparison logic: compare hand types first, then compare card values lexicographically.
  • Edge cases: all cards same suit? No, it's about ranks. Also, consider jokers if part of the problem.
  • Time and space complexity: O(n log n) time, O(n) space.

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.