LeetCode 솔루션					분류
				
						[9/6] 814. Binary Tree Pruning
본문
Medium
3801102Add to ListShareGiven the root of a binary tree, return the same tree where every subtree (of the given tree) not containing a 1 has been removed.
A subtree of a node node is node plus every node that is a descendant of node.
Example 1:

Input: root = [1,null,0,0,1] Output: [1,null,0,null,1] Explanation: Only the red nodes satisfy the property "every subtree not containing a 1". The diagram on the right represents the answer.
Example 2:

Input: root = [1,0,1,0,0,0,1] Output: [1,null,1,null,1]
Example 3:

Input: root = [1,1,0,1,1,0,1,0] Output: [1,1,0,1,1,null,1]
Constraints:
- The number of nodes in the tree is in the range [1, 200].
- Node.valis either- 0or- 1.
Accepted
205,596
Submissions
283,200
관련자료
- 
			링크
			댓글 1
					
			학부유학생님의 댓글
- 익명
- 작성일
					
										
					Runtime: 43 ms, faster than 69.53% of Python3 online submissions for Binary Tree Pruning.
Memory Usage: 14 MB, less than 23.50% of Python3 online submissions for Binary Tree Pruning.
				
													
								Memory Usage: 14 MB, less than 23.50% of Python3 online submissions for Binary Tree Pruning.
# 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 pruneTree(self, root: Optional[TreeNode]) -> Optional[TreeNode]:
        
        if not root: return None
        
        root.left = self.pruneTree(root.left)
        root.right = self.pruneTree(root.right)
        
        if not root.left and not root.right and not root.val: return None
        return root 
								 
							








