题解 | #对称的二叉树#

public class TreeNode {
    int val = 0;
    TreeNode left = null;
    TreeNode right = null;

    public TreeNode(int val) {
        this.val = val;

    }

}
*/
public class Solution {
    boolean isSymmetrical(TreeNode pRoot) {
        if(pRoot==null) return true;
        return isSymmetrical(pRoot.left,pRoot.right);
    }
    boolean isSymmetrical(TreeNode left,TreeNode right){
        if(left==null&&right==null) return true;
        if(left==null||right==null) return false;
        return left.val==right.val
            && isSymmetrical(left.left,right.right)
            && isSymmetrical(left.right,right.left);
    }
}