第89天。
今天的题目是Binary-Tree-Paths:
Given a binary tree, return all root-to-leaf paths.
For example, given the following binary tree:
1
/
2 3
5
All root-to-leaf paths are:
[“1->2->5”, “1->3”]
比较的简单的题目，直接用递归做就好了，因为python写起来比较简单，所以这里用python实现：
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| def binaryTreePaths(self, root):
"""
:type root: TreeNode
:rtype: List[str]
"""
self.ret = []
if root is None:
return self.ret
s = []
self.binaryTreePathsRec(root,s)
return self.ret
def binaryTreePathsRec(self,root,s):
if root is None:
return
s.append(str(root.val))
if root.left is None and root.right is None:
self.ret.append('->'.join(s))
else:
self.binaryTreePathsRec(root.left,s)
self.binaryTreePathsRec(root.right,s)
s.pop()
|