A fresh SQL and Python challenge every day. Practice data engineering skills with adaptive difficulty that matches your level. Track your accuracy, build streaks, and find your weak spots.
The CI/CD team is mapping out when each repository first started running builds. Show each repo alongside its earliest build date, ordered chronologically then alphabetically by repo name.
A square 2D matrix comes back from a tabular export: n rows, n columns, integer cells. Return the values running along the main diagonal, from the top-left corner to the bottom-right. An empty matrix returns an empty list.