Watch less,practice.
Lumicode turns lectures into focused questions, runnable challenges, topic maps, and shareable labs.
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DEMO
Try a real challenge.
30 XP
1
Reachable Rooms
You start in room 0. Each room contains keys to other rooms. Use a stack or DFS to collect reachable rooms, then return True only if none are locked away.
Input:
arg1 = [[1],[2],[3],[]]Returns:
trueInput:
arg1 = [[1,3],[3,0,1],[2],[0]]Returns:
falseInput:
arg1 = [[1,2],[2,3],[3],[]]Returns:
trueInput
arg1 = [[1],[2],[3],[]]
Output
—
Expected
true
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