Applied on the Booking.com website. Received an email explaining the process and a link to HackerRank.com for a test. The link was valid for one week and included four questions. I managed to document two of them.

Identify whether four sides (given by four integers) can form a square, a rectangle, or neither.

Input: Each line of the input describes a single polygon and contains four space-separated integers representing the lengths of its sides. The input lines will follow the 'A B C D' order as in the following representation:

A ------|
       |
D       B
       |
c ------|

Output: A single line containing three space-separated integers representing the number of squares, the number of rectangles, and the number of other polygons with four sides. Squares should not be counted as rectangles. Invalid polygons should also be counted as 'other polygons'.

Constraints: The four integers representing the sides will be such that -2000 <= X <= 2000 (where X represents the integer).

Given a set of hotels and their guest reviews, sort the hotels based on a list of words specified by a user. The criteria for sorting hotels should be how many times the specified words are mentioned in the hotel reviews.

Input: The first line contains a space-separated set of words to find mentions of in the hotel reviews. The second line contains one integer, M, representing the number of reviews. This is followed by M+M lines, alternating between a hotel ID and a review belonging to that hotel.

Output: A list of hotel IDs sorted in descending order by the number of mentions of the specified words. If two hotels have the same number of mentions, they should be sorted by their ID, with the smallest ID first.

Notes:

• The words to be found will always be single words (e.g., 'breakfast' or 'noise'). They will never be phrases (e.g., 'swimming pool').
• Hotel IDs are 4-byte integers.
• Word matches should be case-insensitive.
• Dots and commas should be ignored.
• If a word appears in a review twice, it should count twice.
• In case one or more test cases time out, consider revisiting the runtime complexity of your algorithms.

Given a list of numbers as input, for example: 25626 25757 24367 24267 16 100 2 7277

Produce a delta encoding for the sequence. In a delta encoding, the first element is reproduced as-is. Each subsequent element is represented as the numeric difference from the element before it. For the sequence above, the delta encoding would be: 25626 131 -1390 -100 -24251 84 -98 7275

However, if a difference value does not fit in a single signed byte (i.e., -127 <= x <= 127), then, instead of the difference, an escape token will be used. This token signifies that the value following it is a full four-byte difference value, rather than a one-byte difference value. For this exercise, -128 will be declared as the escape token.

Following the same example, the final output would be: 25626 -128 131 -128 -1390 -100 -128 -24251 84 -98 -128 7275