Tree: Depth-First Search - Invert Binary TreeWhat is the time complexity of the optimal recursive approach to invert a binary tree with n nodes?AO(n^2)BO(n log n)CO(n)DO(log n)Check Answer
Step-by-Step SolutionSolution:Step 1: Analyze traversalThe algorithm visits each node exactly once to swap children.Step 2: Confirm linear timeSince each node is processed once, total time is proportional to n.Final Answer:Option C -> Option CQuick Check:One visit per node -> O(n) time [OK]Quick Trick: One pass over all nodes -> O(n) [OK]Common Mistakes:MISTAKESAssuming O(n log n) due to recursionConfusing with sorting complexitiesTrap Explanation:PITFALLCandidates often overestimate complexity due to recursion overhead, picking O(n log n).Interviewer Note:CONTEXTTests understanding of recursion and traversal complexity
Master "Invert Binary Tree" in Tree: Depth-First Search3 interactive learning modes - each teaches the same concept differentlyTry ItSolutionTrace
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