Problem Description

Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center).

Problem Constraints

1 <= number of nodes <= 10⁵

Input Format

First and only argument is the root node of the binary tree.

Output Format

Return 0 / 1 ( 0 for false, 1 for true ).

Example Input

Input 1:

Input 2:

Example Output

Output 1:

Output 2:

Example Explanation

Explanation 1:

 The above binary tree is symmetric.

Explanation 2:

The above binary tree is not symmetric.