給你一個排序二叉樹和一個n值，把二叉樹分成兩半，一半是<n,另一半>n

package 二叉樹分割;
class Node{
	int num;
	Node lnode,rnode;
	public Node(int num) {
		super();
		this.num = num;
	}
	
}
public class Main {
	static Node min,max;
	public static void fen(Node root,int num){
		if(root==null) return;
		if(root.num==num){
			addNode1(min, root.lnode);
			addNode1(max,root.rnode);
		}else{
			
			if(root.num>num){
				Node left=root.lnode;
				root.lnode=null;
				addNode1(max, root);
				fen(left, num);
			}else{
				Node right=root.rnode;
				root.rnode=null;
				addNode1(min, root);
				fen(right,num);
			}
		}
	}
	public static Node addNode(Node root,int num){
		if(root==null)
			return new Node(num);
		else{
			if(root.num==num) return root;
			if(root.num>num){
				root.lnode=addNode(root.lnode, num);
			}else{
				root.rnode=addNode(root.rnode, num);
			}
			return root;
		}
	}
	public static Node addNode1(Node root,Node newRoot){
		if(newRoot==null)
			return root;
		if(root==null)
			return newRoot;
		else{
			if(root.num>newRoot.num){
				root.lnode=addNode1(root.lnode, newRoot);
			}else{
				root.rnode=addNode1(root.rnode, newRoot);
			}
			return root;
		}
	}
	public static void out(Node root){
		if(root==null) return;
		out(root.lnode);
		System.out.print(root.num+" ");
		out(root.rnode);
	}

	public static void main(String[] args) {
		int[] a={3,1,0,2,4,5,7,21,9};
		Node root=null;
		for(int i=0;i<a.length;++i)
			root=addNode(root, a[i]);
		out(root);
		System.out.println();
		min=new Node(9999);max=new Node(9999);
		int find=8;
		addNode(root,find);
		fen(root, find);
		out(min.lnode);
		System.out.println();
		out(max.lnode);
	}
}