This assessment verifies the Greedy and Advanced Graphs module. Passing it contributes up to 12 points in the 74-85 score band.
Questions
8
Limit
105m
Pass
85%
Score
+12
13 pts
A calendar service wants to accept the maximum number of non-overlapping maintenance windows. A candidate sorts by earliest start time and greedily accepts compatible windows. Review the mistake, give the correct greedy rule, and explain the proof idea.
14 pts
Design the Gas Station solution. Given `gas[i]` and `cost[i]`, return a start index that completes the circuit or `-1`. Explain why restarting after a negative tank is safe.
13 pts
A scheduling service counts meeting rooms by merging overlapping intervals and returning the number of merged blocks. Explain why this is wrong, then design the correct room-count algorithm.
12 pts
A product stores sorted, non-overlapping availability intervals. Insert one new availability interval and return sorted non-overlapping intervals. Describe the three phases and edge cases.
14 pts
A build system has packages and directed dependencies. A candidate uses DFS traversal order from an arbitrary package and says that is enough to build everything. Review the risk and design a topological-sort solution.
9 pts
Which statement is the strongest reason `Course Schedule II` can return an empty order?
14 pts
Given edges of an undirected graph, return the first edge that creates a cycle. Design the Union Find solution and explain what `union` returning false means.
13 pts
A social product receives millions of friendship edges over the day and repeatedly asks whether two users are already in the same connected group. Compare rebuilding DFS/BFS per query with Union Find, and mention the limitation of Union Find.