Coding/symmetric_tree.java at main · shr100/Coding · GitHub

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//Link : https://leetcode.com/problems/symmetric-tree/
/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
    public boolean isSymmetric(TreeNode root) {
        return isMirror(root,root);

    }
    public boolean isMirror(TreeNode node1, TreeNode node2){
        if((node1==null)&&(node2==null)){
            return true;
        }

        if((node1!=null)&&(node2!=null)&&(node1.val==node2.val)){
            return (isMirror(node1.left,node2.right)&&(isMirror(node1.right,node2.left)));
        }
        return false;
    }
}