Determine if the T1 tree has exactly the same subtree as the T2 tree __string

Determine if the T1 tree has exactly the same subtree as the T2 tree public class containsamesubtree{//two fork tree node definition public static class node{public int Valu
		E
		Public Node left;

		public Node right;
		public Node (int data) {this.value=data; }//Solution one to determine whether each subtree in the H1 has the same structure as the H2, Time complexity O (n*m)//To determine whether there is the same subtree (solution two: first serialization, and then use the string KMP matching algorithm, time complexity of O (n+m)) public static
        Boolean Iscontainsamesubtree (Node h1,node h2) {if (H2==null) {return true;
        } if (H1==null) {return false;
        } String Str1=serialbypre (H1);

        String Str2=serialbypre (H2);

	Return Getindexof (STR1,STR2)!=-1; 
        }//First-order traversal serialization binary tree public static String Serialbypre (Node head) {if (head==null) {return "#!";
        } String res=head.value+ "!";
        Res+=serialbypre (Head.left);

        Res+=serialbypre (Head.right);

	return res; }//String matching (KMP algorithm) public static int Getindexof (string s,string m) {if(s==null| | m==null| | M.length () <1| |
    	S.length () <m.length ()) {return-1;
    	///Convert String to array Char[]ss=s.tochararray ();
        
        Char[]ms=m.tochararray ();
        int si=0;
        int mi=0;
        int []next=getnextarray (MS);
        		while (si<ss.length&&mi<ms.length) {if (Ss[si]==ms[mi]) {si++;
        	mi++;
        	else if (next[mi]==-1) {si++;
        	}else{Mi=next[mi];

    } return mi==ms.length?si-mi:-1; ///Get Next array public static Int[]getnextarray (CHAR[]MS) {if (ms.length==1) {return new
       INT[]{-1};
       int []next=new int[ms.length];
       Next[0]=-1;
       next[1]=0;
       int pos=2;
       int cn=0;
       	   while (pos<next.length) {if (MS[POS-1]==MS[CN]) {NEXT[POS++]=++CN;
      else if (cn>0) { 	   	CN=NEXT[CN];
       	   } else{next[pos++]=0;

    } return to Next;
      public static void Main (string[] args) {Node h1=new node (1);
      H1.left=new Node (2);
      H1.right=new Node (3);
      H1.left.left=new Node (4);
      H1.left.right=new Node (5);
      H1.right.left=new Node (6);
      H1.right.right=new Node (7);
      H1.left.left.right=new Node (8);

      H1.left.right.left=new Node (9);
      Node H2=new node (2);
      H2.left=new Node (4);
      H2.right=new Node (5);
      H2.left.right=new Node (8);


      H2.right.left=new Node (9);


	System.out.println (Iscontainsamesubtree (H1,H2)); }
}