Dell Technologies Junior Software Engineer interview questions

Given 2 arrays of numbers, one with N elements, and one with N+1 elements, knowing that the greater one contains all the elements in the smaller one, find the element that isn't on the smaller one.

9 questions in total: 6 theoretical, 3 coding. theoretical Qs included static analysis ex: what this code produces or prints, or whats the problem with the following code, or whats the value of x after execution. Code questions: 1. DNA complement: given a string with length n, made up of A, B, C ,D, change every letter according to the rules, ex: 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 than can be created from swapping digits (unlimited swap operations). 3. Given a binary string, find the number of substrings that contains equal number of 0's and 1's and all 0's and 1's are grouped together, for ex: 1100 is a valid substring, but 0101 isn't (although number of zeroes are equal to ones, but the digits aren't grouped together)