One phone screen, followed by four onsite interviews if selected. These are technical interviews. An exploratory call occurred at first.

Things to look out for:

• Gather requirements before starting any assessments.
• Provide alternative solutions and trade-offs before choosing one.
• Communicate through your coding, letting the team know what you're doing.
• Look for corner cases.

Find the number of islands.

This is a variation of the standard problem: “Counting the number of connected components in an undirected graph.”