1. public static class Node {
    2.         public int value;
    3.         public Node left;
    4.         public Node right;
    6.         public Node(int data) {
    7.             this.value = data;
    8.         }
    9.     }
    11.     public static boolean isBalanced1(Node head) {
    12.         boolean[] ans = new boolean[1];
    13.         // 假设是true
    14.         ans[0] = true;
    15.         process1(head, ans);
    16.         return ans[0];
    17.     }
    19.     public static int process1(Node head, boolean[] ans) {
    20.         if (!ans[0] || head == null) {
    21.             return -1;
    22.         }
    23.         // 左树要信息
    24.         int leftHeight = process1(head.left, ans);
    25.         // 右树要信息
    26.         int rightHeight = process1(head.right, ans);
    27.         // 左高-右高>1，则false
    28.         if (Math.abs(leftHeight - rightHeight) > 1) {
    29.             ans[0] = false;
    30.         }
    31.         return Math.max(leftHeight, rightHeight) + 1;
    32.     }