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”]
Credits:
Special thanks to @jianchao.li.fighter for adding this problem and creating all test cases.
这种第一时间想到的就是递归啦。考虑好结束条件,就是左右子树都为空即叶子节点为结束条件,依次递归,不过要考虑好字符串的处理问题。
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode(int x) { val = x; }
* }
*/
public class