创建一颗二叉树，并且可以用前序、中序、后序进行遍历。-Create a binary tree, and you can preorder, inorder, and postorder traversal.

树的创建和遍历，包含前序遍历，中序遍历和后序遍历，并找出某个以前的所有祖先-The creation of a tree and ergodic, including preorder traversal, the sequence traversal and the sequence traversal, and find out a previous all ancestors