Question
Consider all the leaves of a binary tree, from left to right order, the values of those leaves form a leaf value sequence.
For example, in the given tree above, the leaf value sequence is (6, 7, 4, 9, 8)
.
Two binary trees are considered leaf-similar if their leaf value sequence is the same.
Return true
if and only if the two given trees with head nodes root1
and root2
are leaf-similar.
Example 1:
Input: root1 = [3,5,1,6,2,9,8,null,null,7,4], root2 = [3,5,1,6,7,4,2,null,null,null,null,null,null,9,8] Output: true
Example 2:
Input: root1 = [1,2,3], root2 = [1,3,2] Output: false
Constraints:
- The number of nodes in each tree will be in the range
[1, 200]
. - Both of the given trees will have values in the range
[0, 200]
.
Python Solution
# 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 make_list(self,root,l): if root == None: return self.make_list(root.left,l) if root.left==None and root.right==None: l.append(root.val) self.make_list(root.right,l) def leafSimilar(self, root1: TreeNode, root2: TreeNode) -> bool: l1 = [] l2 = [] self.make_list(root1,l1) self.make_list(root2,l2) return l1==l2