public boolean isSameTree(TreeNode p, TreeNode q) {
		 	if(p !=null && q !=null){
		 		if(p.val == q.val){
			 		return isSameTree(p.left , q.left) && isSameTree(p.right , q.right);
			 	}else{
			 		return false;
			 	}
		 	}else if(p ==null && q == null){
			 	return true;
		 	}else{
		 		return false;
		 	}
	 	}