check similarity of two structures

#include<iostream>
using namespace std;

class Node{
  public:
      int data;
      Node *left,*right;
      Node(int key){
        data=key;
        left=NULL;
        right=NULL;
        }
  };

int CheckSimilarity(Node *root1,Node *root2){
  if(root1==NULL && root2==NULL)
    return 1;
  if(root1==NULL || root2==NULL)
    return 0;
  return(CheckSimilarity(root1->left,root2->left) && CheckSimilarity(root1->right,root2->right));
  }


int main(){
  Node *root1=NULL;
  Node *newnode=new Node(1);
  root1=newnode;
  root1->left=new Node(2);
  root1->right=new Node(3);
  (root1->left)->left=new Node(4);
  (root1->right)->right=new Node(5);
  ((root1->left)->left)->left=new Node(6);

  Node *root2=NULL;
  Node *node=new Node(7);
  root2=node;
  root2->left=new Node(8);
  root2->right=new Node(9);
  (root2->left)->left=new Node(10);
  (root2->right)->right=new Node(11);
  ((root2->left)->left)->left=new Node(12);
  int result=CheckSimilarity(root1,root2);
  if(result==1)
    cout<<"both structures are similar";
  else
    cout<<"both structures are not similar";
  return 0;
  }