Introduction - If you have any usage issues, please Google them yourself
A non-empty binary tree can be seen from the root node, the left subtree and right subtree consists of three basic parts. If you can turn these three sections traversing information, it traverses the entire binary tree. The thus obtained binary tree traversal strategy is based on a binary tree for each access point and the access node process only once. Binary tree traversal root-access priority sequence is divided into three different preorder, inorder and post.