Online Assessment: Three Coding Questions

This online assessment consists of three distinct coding questions to be completed within a 90-minute timeframe. You are required to implement solutions for all questions.

Question 1: Group Anagrams

Given an array of strings, strs, group the strings into lists where each list contains strings that are anagrams of each other.

Input

• strs: An array of lowercase strings, which may include duplicates.

Output

• A list of groups, where each group is itself a list of strings. The order of groups and the order of strings within a group do not matter.

Constraints

• 1 <= len(strs) <= 10^4
• 0 <= len(strs[i]) <= 100

Question 2: Maximize Integer by Swapping Two Digits

Given a non-negative integer num, you may swap at most one pair of its digits (or perform no swap). Return the maximum value you can obtain.

Input

• num: A non-negative integer.

Output

• The maximum integer achievable after performing at most one swap.

Constraints

• 0 <= num <= 10^8

Question 3: Rank Hotels by Review Sentiment and Return Top K

You are provided with a set of positive keywords, a set of negative keywords, a list of hotel reviews each associated with a hotel_id, and an integer k. Your task is to compute each hotel’s total sentiment score by scanning all its reviews and then return the top k hotel IDs.

Scoring Rules

• Each review must be tokenized into words by splitting on any non-letter characters (punctuation and symbols act as separators).
• Word comparisons are case-insensitive.
• For every word occurrence:
  • If the word is in the positive keyword set, add +1 to the score.
  • If the word is in the negative keyword set, add -1 to the score.
  • Otherwise, add 0.
• A hotel’s total score is the sum of scores across all its associated reviews.

Task

Return an array of the top k hotel IDs, ranked by:

1. Higher total score first.
2. If total scores are tied, smaller hotel_id first.

Input

• positive_keywords: A string or list of words representing positive sentiment.
• negative_keywords: A string or list of words representing negative sentiment.
• hotel_ids: An array of integers, where hotel_ids[i] corresponds to the hotel ID for reviews[i].
• reviews: An array of strings, where reviews[i] is a review text.
• k: An integer representing the number of top hotels to return.

Output

• An array of k hotel IDs in the specified sorted ranking order.

Constraints

• 1 <= len(reviews) == len(hotel_ids) <= 10^5
• Total length of all review texts combined is up to approximately 10^6 characters.
• 1 <= k <= number_of_distinct_hotels

Notes

• If a hotel has multiple reviews, their scores must be aggregated.
• If there are fewer than k distinct hotels, return all available hotels sorted by the same rules.