给定一个二叉树,返回所有从根节点到叶子节点的路径。
说明: 叶子节点是指没有子节点的节点。
示例:
输入:
1
/ \
2 3
\
5
输出: ["1->2->5", "1->3"]
解释: 所有根节点到叶子节点的路径为: 1->2->5, 1->3
/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
class Solution {
public:
vector<string> binaryTreePaths(TreeNode* root) {
if (root == NULL)
return {};
vector<string> leftPaths = binaryTreePaths(root->left);
vector<string> rightPaths = binaryTreePaths(root->right);
vector<string> paths;
for (auto p: leftPaths)
paths.push_back(to_string(root->val) + "->" + p);
for (auto p: rightPaths)
paths.push_back(to_string(root->val) + "->" + p);
if (paths.empty())
paths.push_back(to_string(root->val));
return paths;
}
};