Which approach guarantees an optimal solution that efficiently checks this property by comparing nodes in a mirrored fashion?
easy🔍 Pattern Recognition Q11 of Q15
Tree: Depth-First Search - Symmetric Tree (DFS Approach)
You are given a binary tree and need to determine if it is a mirror of itself (i.e., symmetric around its center). Which approach guarantees an optimal solution that efficiently checks this property by comparing nodes in a mirrored fashion?
AUse a recursive DFS that simultaneously compares the left subtree of one node with the right subtree of the other node, returning false immediately on mismatch.
BPerform a level-order traversal and compare nodes at each level from left to right.
CTraverse the tree in preorder and check if the sequence of node values is a palindrome.
DUse a brute force approach that generates all subtree permutations and checks for symmetry.
Step-by-Step Solution
Solution:
Step 1: Understand the problem requires mirrored subtree comparison
The problem asks if the tree is symmetric, meaning the left subtree is a mirror reflection of the right subtree.
Step 2: Identify the approach that compares mirrored nodes recursively with early exit
The recursive DFS approach compares left subtree nodes with right subtree nodes in mirrored positions and returns false immediately if any mismatch is found, ensuring efficiency.
Final Answer:
Option A -> Option A
Quick Check:
Mirrored recursive DFS matches problem requirements [OK]
