Dell: Technical Screening Assessment

Received an email with a link to a HackerRank test. It contained 9 questions: 6 theoretical and 3 technical (coding problems). The entire test had a 90-minute time limit.

9 questions in total: 6 theoretical, 3 coding.

Theoretical questions included static analysis, for example:

• What this code produces or prints.
• What's the problem with the following code.
• What's the value of x after execution.

Coding questions:

1. DNA complement: Given a string of length n, made up of A, B, C, D. Change every letter according to the rules (e.g., A becomes B, B becomes D, and so on). Input: AB -> Output: BD

2. Given a number num. Two adjacent digits can be swapped if they are both odd OR if they are both even. Find the largest number that can be created from swapping digits (unlimited swap operations).

3. Given a binary string, find the number of substrings that contain an equal number of 0's and 1's, and all 0's and 1's are grouped together. For example, "1100" is a valid substring, but "0101" isn't (although the number of zeroes equals the number of ones, the digits aren't grouped together).