The interview process began with a basic phone screen covering visa status, GPA, and standard behavioral questions. Following the phone screen, candidates were asked to complete a HackerRank challenge and were scheduled for a technical phone interview the subsequent week.

The HackerRank challenge included the following questions:

1. Given a list of strings, return the words that can be typed using only one row of a keyboard. For example: ["Hello", "Alaska", "Dad", "Peace"] => ["Alaska", "Dad"].
2. Given a list of strings containing operators and numbers, determine the sum of the given expression. The numbers can be positive or negative, and the operators are limited to multiplication and division.
3. Given an array starting from 1 to 2^n (e.g., [1, 2, 3, 4]), transform the array such that when split in half, the left side is placed on top of the right. Repeat this process until the left side has a length of 1. Example: [1, 2, 3, 4] => [1, 2][3, 4] => [1][3][2][4] => [1, 3, 2, 4].
4. Given a graph of vertices and directed edges, return all vertices in order that can visit all other vertices within 2 steps.

The technical interview focused on designing a class for humans and pets. Candidates were questioned about the time complexity of the algorithms they wrote on HackerRank and were presented with additional problems related to the HackerRank questions.

1. Given a list of strings, return the words that can be typed using only one row of your keyboard. Example: ["Hello", "Alaska", "Dad", "Peace"] => ["Alaska", "Dad"]

2. Given a list of strings containing operators and numbers, determine the sum of the given expression. The numbers can be positive or negative, and the operators only include multiplication and division.

3. Given an array starting from 1 to 2^n, for example, [1, 2, 3, 4], transform the array such that when you split it in half, the left side goes on top of the right. Repeat this until the left side has a length of 1. [1, 2, 3, 4] => [1, 2][3, 4] => [1][3][2][4] => [1, 3, 2, 4].

4. Given a graph of vertices and directed edges, return all vertices in order that can visit all other vertices within 2 steps.