[Javase] Data structure (binary lookup tree-insert node)

Binary search tree,also known as binary searching tree, is a special two-fork tree, and the node value of Zuozi is less than the node value of the right subtree.

Define a binary lookup tree

Defines the binary tree bstree, which protects the mroot of the root node of the two fork tree bstnode type , defines the inner class Bstnode

Contains several basic information about the two-fork tree:

key--keyword used to sort the nodes of a two-fork lookup tree

left--the child that points to the current node

right--the child pointing to the current node

Parent--points to the parents of the current node

Define Insert Node Method insert (t key), parameter:T key the object to insert

Create a Node object, instantiate a bstnode object, construct a parameter:T Object

Define overloaded methods Insert (Bstree bstree,bstnode bstnode) method, Parameters:bstree Tree object,Bstnode Node Object

Insert a node in two steps,

1. Find the parent node location of the node

2. Insert the node to the left or right position of the parent node

 Public classBstree<textendsComparable<t>> {    PrivateBstnode<t>Mroot; /*** Define binary tree * *@authorTaoshihan *@param<T> **/     Public classBstnode<textendsComparable<t>> {         PublicT Key;  PublicBstnode Parent, left, right;  PublicBstnode (T key, Bstnode parent, Bstnode left, Bstnode right) { This. Key =key;  This. Parent =parent;  This. left =Left ;  This. right =Right ; }    }     Public voidInsert (Bstree bstree, Bstnode Bstnode) {Bstnode parent=NULL; Bstnode x=Bstree.mroot; //to find the insertion position of the Bstnode, the x pointer refers to the         while(X! =NULL) {Parent= x;//The position of X as the parent class of the node            intFlag =BstNode.key.compareTo (X.key); if(Flag < 0) {x=X.left; }Else{x=X.right; }        }        //InsertBstnode.parent =parent; if(parent==NULL) {Bstree.mroot=Bstnode; }Else{            intFlag =BstNode.key.compareTo (Parent.key); if(Flag < 0) {Parent.left=Bstnode; } Else{parent.right=Bstnode; }                }    }    /*** Insert Root node * *@paramKey*/     Public voidInsert (T key) {Bstnode<T> z =NewBstnode<t> (Key,NULL,NULL,NULL); //If the new node fails, it is returned.         if(Z! =NULL) Insert ( This, z); }    /** print "binary lookup tree" * * Key--node key value * Direction--0, indicating that the node is the root node;     *-1, which indicates that the node is the left child of its parent junction;     * 1, which indicates that the node is the right child of its parent node. */    Private voidPrint (bstnode<t> tree, T key,intdirection) {                if(Tree! =NULL) {            if(direction==0)//tree is the root nodeSystem.out.printf ("%2d is root\n", Tree.key); Else                //Tree is a branch nodeSystem.out.printf ("%2d is%2d ' s%6s child\n", Tree.key, Key, Direction==1? " Right ":" Left "); Print (Tree.left, Tree.key,-1); Print (Tree.right,tree.key,1); }    }     Public voidPrint (bstree<t>tree) {        if(Tree.mroot! =NULL) {print (Tree.mroot, Tree.mRoot.key,0); }    }    /**     * @paramargs*/     Public Static voidMain (string[] args) {Bstree tree=NewBstree (); Tree.insert (3); Tree.insert (1); Tree.insert (2); Tree.insert (5); Tree.insert (4); Tree.insert (6);    Tree.print (tree); }}

Output:

3 is root
1 is 3 ' s left child
2 is 1 ' s right child
5 is 3 ' s right child
4 is 5 ' s left child
6 is 5 ' s right child

[Javase] Data structure (binary lookup tree-insert node)