Given a binary tree, determine if it is height-balanced.   Example 1: Input: root = [3,9,20,null,null,15,7] Output: true Example 2: Input: root = [1,2,2,3,3,null,null,4,4] Output: false Example 3: Input: root = [] Output: true   Constraints:

给你一棵二叉搜索树，请你返回一棵 平衡后 的二叉搜索树，新生成的树应该与原来的树有着相同的节点值。如果有多种构造方法，请你返回任意一种。 如果一棵二叉搜索树中，每个节点的两棵子树高度差不超过 1 ，我们就称这棵二叉搜索树是 平衡的 。   示例 1： 输入：root = [1,null,2,null,3,null,4,null,null] 输出：[2,1,3,null,null,null,4] 解释：这不是唯一的正确答案，[3,1,4,null,2,null,null] 也是一个可行的构造方案。 示例 2：…

Given the root of a binary search tree, return a balanced binary search tree with the same node values. If there is more than one answer, return any of them. A binary search tree is balanced if the depth of the two subtrees of every node never differs by…

给你一个整数数组 nums。

You are given an integer array nums. A subarray is called balanced if the number of distinct even numbers in the subarray is equal to the number of distinct odd numbers. Return the length of the longest balanced subarray.   Example 1: Input: nums = [2,5,4…

给你一个整数数组 nums。

You are given an integer array nums. A subarray is called balanced if the number of distinct even numbers in the subarray is equal to the number of distinct odd numbers. Return the length of the longest balanced subarray.   Example 1: Input: nums = [2,5,4…

给你一个由小写英文字母组成的字符串 s。

You are given a string s consisting of lowercase English letters. A substring of s is called balanced if all distinct characters in the substring appear the same number of times. Return the length of the longest balanced substring of s.   Example 1: Input:…

给你一个只包含字符 'a'、'b' 和 'c' 的字符串 s。

You are given a string s consisting only of the characters 'a', 'b', and 'c'. A substring of s is called balanced if all distinct characters in the substring appear the same number of times. Return the length of the longest balanced substring of s.   Example…

我们把玻璃杯摆成金字塔的形状，其中 第一层 有 1 个玻璃杯， 第二层 有 2 个，依次类推到第 100 层，每个玻璃杯将盛有香槟。 从顶层的第一个玻璃杯开始倾倒一些香槟，当顶层的杯子满了，任何溢出的香槟都会立刻等流量的流向左右两侧的玻璃杯。当左右两边的杯子也满了，就会等流量的流向它们左右两边的杯子，依次类推。（当最底层的玻璃杯满了，香槟会流到地板上） 例如，在倾倒一杯香槟后，最顶层的玻璃杯满了。倾倒了两杯香槟后，第二层的两个玻璃杯各自盛放一半的香槟。在倒三杯香槟后，第二层的香槟满了 - 此时总共有三个…

We stack glasses in a pyramid, where the first row has 1 glass, the second row has 2 glasses, and so on until the 100th row.  Each glass holds one cup of champagne. Then, some champagne is poured into the first glass at the top.  When the topmost glass is…

给你两个二进制字符串 a 和 b ，以二进制字符串的形式返回它们的和。   示例 1： 输入:a = "11", b = "1" 输出："100" 示例 2： 输入：a = "1010", b = "1011" 输出："10101"   提示：

Given two binary strings a and b, return their sum as a binary string.   Example 1: Input: a = "11", b = "1" Output: "100" Example 2: Input: a = "1010", b = "1011" Output: "10101"   Constraints:

颠倒给定的 32 位有符号整数的二进制位。   示例 1： 输入：n = 43261596 输出：964176192 解释：

Reverse bits of a given 32 bits signed integer.   Example 1: Input: n = 43261596 Output: 964176192 Explanation:

二进制手表顶部有 4 个 LED 代表 小时（0-11），底部的 6 个 LED 代表 分钟（0-59）。每个 LED 代表一个 0 或 1，最低位在右侧。

A binary watch has 4 LEDs on the top to represent the hours (0-11), and 6 LEDs on the bottom to represent the minutes (0-59). Each LED represents a zero or one, with the least significant bit on the right.

给定一个正整数，检查它的二进制表示是否总是 0、1 交替出现：换句话说，就是二进制表示中相邻两位的数字永不相同。   示例 1： 输入：n = 5 输出：true 解释：5 的二进制表示是：101 示例 2： 输入：n = 7 输出：false 解释：7 的二进制表示是：111. 示例 3： 输入：n = 11 输出：false 解释：11 的二进制表示是：1011.   提示：

Given a positive integer, check whether it has alternating bits: namely, if two adjacent bits will always have different values.   Example 1: Input: n = 5 Output: true Explanation: The binary representation of 5 is: 101 Example 2: Input: n = 7 Output: false…