Method height

Java/Balanced-Binary-Tree.java:34–45

(TreeNode root)

    }
    
    private int height(TreeNode root){
        // calculate the height of a tree
        if(root == null){
            return 0;
        }
        else{
            int left = height(root.left);
            int right = height(root.right);
            int height = left > right ? left : right;
            return height + 1;
        }
    }
}