二叉树任意两个节点的最近公共祖先

import java.util.Scanner;
public class Main {
    public static class TreeNode{
        int val;
        TreeNode leftTreeNode;
        TreeNode rightTreeNode;
        public TreeNode(int n){
            this.val=n;
        }
    }
    public static void main(String[] args) {
        // Scanner input=new Scanner(System.in);
        // String str=input.next();
        System.out.println("hello world");
        TreeNode root=makeTree();
        int result=findParent(root, 8, 5);
        System.out.println(result);
    }
    public static int findParent(TreeNode root, int a, int b){
        if(root==null){
            return -1;
        }
        // find a or b
        if(root.val==a||root.val==b){
            return root.val==a?a:b;
        }
        int one=findParent(root.leftTreeNode, a, b);
        int two=findParent(root.rightTreeNode, a, b);
        // if left tree find a , right tree find b
        if((one==a&&two==b) || (one==b&&two==a)){
            return root.val;
        }else{
            // if find one
        }
        return -1;
    }
    public static TreeNode makeTree(){
        TreeNode node1=new TreeNode(1);
        TreeNode node2=new TreeNode(2);
        TreeNode node3=new TreeNode(3);
        TreeNode node4=new TreeNode(4);
        TreeNode node5=new TreeNode(5);
        TreeNode node6=new TreeNode(6);
        TreeNode node7=new TreeNode(7);
        TreeNode node8=new TreeNode(8);
        TreeNode node9=new TreeNode(9);
        node1.leftTreeNode=node2;
        node1.rightTreeNode=node3;
        node2.leftTreeNode=node4;
        node2.rightTreeNode=node5;
        node4.leftTreeNode=node8;
        node4.rightTreeNode=node9;
        node3.leftTreeNode=node6;
        node3.rightTreeNode=node7;
        return node1;
    }
}