<p>Consider all the leaves of a binary tree, from&nbsp;left to right order, the values of those&nbsp;leaves form a <strong>leaf value sequence</strong><em>.</em></p>

<p><img alt="" src="https://s3-lc-upload.s3.amazonaws.com/uploads/2018/07/16/tree.png" style="width: 400px; height: 336px;" /></p>

<p>For example, in the given tree above, the leaf value sequence is <code>(6, 7, 4, 9, 8)</code>.</p>

<p>Two binary trees are considered <em>leaf-similar</em>&nbsp;if their leaf value sequence is the same.</p>

<p>Return <code>true</code> if and only if the two given trees with head nodes <code>root1</code> and <code>root2</code> are leaf-similar.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2020/09/03/leaf-similar-1.jpg" style="width: 600px; height: 237px;" />
<pre>
<strong>Input:</strong> 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]
<strong>Output:</strong> true
</pre>

<p><strong class="example">Example 2:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2020/09/03/leaf-similar-2.jpg" style="width: 300px; height: 110px;" />
<pre>
<strong>Input:</strong> root1 = [1,2,3], root2 = [1,3,2]
<strong>Output:</strong> false
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li>The number of nodes in each tree will be in the range <code>[1, 200]</code>.</li>
	<li>Both of the given trees will have values in the range <code>[0, 200]</code>.</li>
</ul>

# 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 leafSimilar(self, root1: Optional[TreeNode], root2: Optional[TreeNode]) -> bool:
        leaf1, leaf2 = [], []
        
        def get_leaves(root, leaf):
            if not root:
                return 

            if root.left:
                get_leaves(root.left, leaf)
            if root.right:
                get_leaves(root.right, leaf)
            if not root.left and not root.right:
                leaf.append(root.val)

        get_leaves(root1, leaf1)
        get_leaves(root2, leaf2)

        return True if leaf1 == leaf2 else False
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