While most technical hiring questions aren’t all that relevant, this one might be more generally useful. Find duplicate files; the trick was the speedup..
Learning a new computer language can be fun! Stretching ourselves to think about problems in new ways..
Building interactive commands that uses editing history and tab completion can be easy in bash and serve as a wrapper for automating tasks.
I keep a large framed photo of this on the wall in my office to remind me what can happen when things go “off the rails”..
A colleague of mine once posted a hiring question to ask prospective developers: “What is the least significant 10 digits of the series: .. ?”
Many people use awk for one-liners; picking out fields from logs, doing pattern matching. It’s capable of so much more however. IMO, the “littleness” of the language is one of it’s strengths.
Just for fun, how many combinations of months are there where Friday falls on the 13th? This one-liner will print out a table of month combinations along with the years for a given range.