剑指 Offer 55 - II. 平衡二叉树

package leetcode;

public class offer_55_2 {
    public boolean isBalanced(TreeNode root) {
        if(root==null) {
            return true;
        }
        return isBalanced(root.left)&&isBalanced(root.right)&&Math.abs(treeHeight(root.left)-treeHeight(root.right))<=1;
    }
    
    public int treeHeight(TreeNode root) {
        return root==null?0:Math.max(treeHeight(root.left),treeHeight(root.right))+1;
    }
}