二叉搜索树（java）

二叉搜索树可以算是基于二叉排序树的，差别在于其中有个查找（其实也就是递归遍历），所以可以说跟二叉排序是基本一致的。

上代码：

class TreeNode {
    int value;
    TreeNode left_node;
    TreeNode right_node;
    public TreeNode(int value) {
        this.value = value;
        this.left_node = null;
        this.right_node = null;
    }
}

public class BinarySearchTree {
    public TreeNode rootNode;
    public static int count = 1;

    public void Add_Node_To_Tree(int value) {
        if(rootNode == null) {
            rootNode = new TreeNode(value);
            return;
        }
        TreeNode currentNode = rootNode;
        while (true) {
            if(value < currentNode.value) {
                if(currentNode.left_node == null) {
                    currentNode.left_node = new TreeNode(value);
                    return;
                }
                else {
                    currentNode = currentNode.left_node;
                }
            }
            else {
                if(currentNode.right_node == null) {
                    currentNode.right_node = new TreeNode(value);
                    return;
                }
                else {
                    currentNode = currentNode.right_node;
                }
            }
        }
    }

    public boolean findTree(TreeNode node, int value) {
        if(node == null) {
            return false;
        }
        else if(node.value == value) {
            System.out.println("共搜索" + count + "次");
            return true;
        }
        else if(value < node.value) {
            count+=1;
            return findTree(node.left_node, value);
        }
        else {
            count+=1;
            return findTree(node.right_node, value);
        }
    }

    public static void main(String[] args) throws IOException {
        int i, value;
        BinarySearchTree tree = new BinarySearchTree();
        int arr[] = {7, 4, 1, 5, 13, 8, 11, 12, 15, 9, 2};
        System.out.println("原型数组内容：");
        for(i=0;i<11;i++) {
            System.out.print("[" + arr[i] + "]");
        }
        System.out.println();
        for (i=0;i<11;i++) {
            tree.Add_Node_To_Tree(arr[i]);
        }
        System.out.print("请输入搜索值： ");
        BufferedReader keyin = new BufferedReader(new InputStreamReader(System.in));
        value = Integer.parseInt(keyin.readLine());
        if(tree.findTree(tree.rootNode, value)) {
            System.out.println("您要找的值 [" + value + "] 已经找到！");
        } else {
            System.out.println("抱歉没有找到！");
        }
    }
}