James Pan

原题网址：https://leetcode.com/problems/flatten-binary-tree-to-linked-list/Given a binary tree, flatten it to a linked list in-place.For example,Given 1 / \ 2 5

原题网址：https://leetcode.com/problems/invert-binary-tree/Invert a binary tree. 4 / \ 2 7 / \ / \1 3 6 9to 4 / \ 7 2 / \ / \9 6 3 1思路：递归调用，对左右子节

原题网址：https://leetcode.com/problems/find-leaves-of-binary-tree/Given a binary tree, find all leaves and then remove those leaves. Then repeat the previous steps until the tree is empty.Example:

原题网址：https://leetcode.com/problems/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 em

原题网址：https://leetcode.com/problems/delete-node-in-a-bst/Given a root node reference of a BST and a key, delete the node with the given key in the BST. Return the root node reference (possibly up