生成随机id 最近公司的项目游戏生成的随机不重复id,重复概率有点大, 代码如下: private static int id = 0; public static int serverID = 0; private static final Object obj = new Object(); public static long getId1() { synchronized (obj) { id += 1; return (serverID & 0xFFFF) << 48 | (
Design a data structure that supports all following operations in averageO(1) time. Note: Duplicate elements are allowed. insert(val): Inserts an item val to the collection. remove(val): Removes an item val from the collection if present. getRandom:
设计一个支持在平均 时间复杂度 O(1) 下, 执行以下操作的数据结构.注意: 允许出现重复元素. insert(val):向集合中插入元素 val. remove(val):当 val 存在时,从集合中移除一个 val. getRandom:从现有集合中随机获取一个元素.每个元素被返回的概率应该与其在集合中的数量呈线性相关.示例:// 初始化一个空的集合.RandomizedCollection collection = new RandomizedCollection();
题目: Design a data structure that supports all following operations in averageO(1) time. Note: Duplicate elements are allowed. insert(val): Inserts an item val to the collection. remove(val): Removes an item val from the collection if present. getRand
经测试,最快的一种 public class Generator { // should be between 40 (34 years) and 42 (139 years) ; // should be between 0 (single generator) and 10 (1024 generators) ; // should be 10 at least (4096 unique ids per millisecond per generator) - NumberOfTimeBit