110. 平衡二叉树 Java版

class Solution {
    public boolean isBalanced(TreeNode root) {

        if(root==null){
            return true;
        }

        int leftDepth = depth(root.left);
        int rightDepth = depth(root.right);

        return Math.abs(leftDepth-rightDepth)>1 ? false:isBalanced(root.left) && isBalanced(root.right);

    }

    public int depth(TreeNode root){
        
        if(root == null)
            return 0;

        return Math.max(depth(root.left),depth(root.right))+1;
    }
}