649. Binary Tree Upside Down
Given a binary tree where all the right nodes are either leaf nodes with a sibling (a left node that shares the same parent node) or empty, flip it upside down and turn it into a tree where the original right nodes turned into left leaf nodes. Return the new root. Have you met this question in a real interview? Yes Problem Correction Example Example1 Given a binary tree {1,2,3,4,5} 1 / \ 2 3 / \ 4 5 return the root of the binary tree {4,5,2,#,#,3,1} . 4 / \ 5 2 / \ 3 1 Example2 Given a binary tree {1,2,3,4} 1 / \ 2 3 / 4 return the root of the binary tree {4,#,2,3,1} . 4 \ 2 / \ 3 1 class Solution { public : /** * @param root: the root of binary tree * @return: new root */ TreeNode * upsideDownBinaryTree (TreeNode * root) { // write your code here //典型的recursion啊,但不太好想 if (root == NULL || (root-...