Graph problems that keep appearing in interviews - a compilation

After giving 15+ interviews this year, here are graph problems I've seen repeatedly:

BFS/DFS based:

• Number of islands
• Clone graph
• Word ladder
• Rotten oranges

Shortest path:

• Network delay time (Dijkstra)
• Cheapest flights within K stops

Topological Sort:

• Course schedule I and II
• Alien dictionary

Union Find:

• Number of connected components
• Accounts merge

If you can solve all of these comfortably, you'll handle 90% of graph questions in interviews imo.