Other 路 Intern to senior
Coding rounds test whether you can turn a problem into working code and talk about its cost. Start with a correct solution, state its time and space complexity, then improve it. Interviewers care about your reasoning as much as the final code.
2 of 3 questions match
Clear filtersWalk through the array once while storing each number鈥檚 index in a hash map; for every number, check whether target minus that number is already in the map. This runs in O(n) time and O(n) space.
Recursively walk the array: when an element is an array, flatten it and append the result; otherwise append the element. An iterative version uses an explicit stack to avoid recursion limits.