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

    }