c_cpp 145. Binary Tree Postorder Traversal - DifficultyHard - 2018.9.7

Posted 2021-05-14

//递归解法：
class Solution {
public:
    void pTra(TreeNode* root, vector<int> &vec) {
        if (root == NULL) return;
        pTra(root->left, vec);
        pTra(root->right, vec);
        vec.insert(vec.end(), root->val);
    }
    vector<int> postorderTraversal(TreeNode* root) {
        vector<int> result;
        pTra(root, result);
        return result;
    }
};