Symmetric Tree

class Node {
    int data;
    Node left;
    Node right;

    Node(int data) {
        this.data = data;
        left = null;
        right = null;
    }
}

class Solution {
    public boolean isSymmetric(Node root) {
        if (root == null)
            return true;

        return check(root.left, root.right);
    }

    public static boolean check(Node head1, Node head2) {
        if (head1 == null && head2 == null)
            return true;
        if (head1 == null || head2 == null || head1.data != head2.data)
            return false;

        boolean left = check(head1.left, head2.right);
        boolean right = check(head1.right, head2.left);
        return left && right;
    }
}