hims & hers·Software Engineer·Technical Phone Screen
Jun 2026
Coding round at hims & hers with a classic array problem that has a neat in-place trick most people either know or don't.
- Given an integer array of length n where every value is between 1 and n and each value appears once or twice, find all the duplicates. Must run in O(n) time with constant extra space.
“I knew this one but blanked on articulating why the negation trick works under the space constraint.”