[NeetCode/Python] Invert a Binary Tree

문제: https://neetcode.io/problems/invert-a-binary-tree

NeetCode

 

[내 코드]

# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right

class Solution:
    def invertTree(self, root: Optional[TreeNode]) -> Optional[TreeNode]:
        if not root:
            return
        temp = root.left
        root.left = root.right
        root.right = temp

        self.invertTree(root.left)
        self.invertTree(root.right)

        return root

 

 

[솔루션 코드]

# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right

class Solution:
    def invertTree(self, root: Optional[TreeNode]) -> Optional[TreeNode]:
        if not root: return None

        root.left, root.right = root.right, root.left
        
        self.invertTree(root.left)
        self.invertTree(root.right)
        
        return root

솔루션이랑 거의 똑같이 풀었다~

이제 대입할 때 python은 저렇게 콤마로 각각 대입이 된다는걸 다시 기억하자!

 

 

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