PTA 是否同一棵二叉搜索树 java

package pat树;
//ac
//参考博客
//javascript:void(0)
import java.util.Scanner;

public class Main2是否同一棵二叉搜索树 {
    static int n;
    static int m;
    static int[]arr;
    public static boolean charge(node i,node j) {
        if(i!=null&&j!=null) {
            if(i.v==j.v)return charge(i.le,j.le)&&charge(i.ri,j.ri);
            else return false;
        }
        else if(i==null&&j==null)return true;
        else return false;
    }
    public static node insert(node root,int i) {
        if(root==null) {
            root=new node();
            root.v=arr[i];
            return root;
        }
        else {
            if(arr[i]>root.v) {
                root.ri=insert(root.ri,i);
            }
            else {
                root.le=insert(root.le,i);
            }
            return root;
        }
    }
    public static node build() {
        node root=null;
        for(int i=0;i<n;i++)root=insert(root,i);
        return root;
    }
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        while(in.hasNext()) {
            n=in.nextInt();
            if(n==0)break;
            m=in.nextInt();
            arr=new int[n];
            for(int i=0;i<n;i++)arr[i]=in.nextInt();
            node root=build();
            for(int i=0;i<m;i++) {
                for(int j=0;j<n;j++) {
                    arr[j]=in.nextInt();
                }
                node rootsecond=build();
                if(charge(root,rootsecond))System.out.println("Yes");
                else System.out.println("No");
            }           
        }     
    }
}
class node{
    int v;
    node le;
    node ri;
}