有趣的抢红包算法

算法原理

今天分享一篇有趣的抢红包算法，基本原理就是“二倍均值”，简单说，也就是一个公式，在这里，令P为人数，M为红包总金额，那么每次抢到的红包金额=随机区间（0，P/Mx2），这样才可以保证每次抢到随机金额的均值是相等的。

代码展示

package Sort_normal;

import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import java.util.Scanner;

// M:剩餘紅包
// N:剩餘金額
// 每次搶到金額：隨機區間[0,M/Nx2]
public class Red_Package {
 public static void main(String[] args) {
 Scanner in = new Scanner(System.in);
 System.out.println("请输入红包金额：");
 Integer TotalAmount = in.nextInt();
 System.out.println("请输入人数：");
 Integer TotalPeople = in.nextInt();
 List<Integer> amountList = RedPackage(TotalAmount, TotalPeople);
// String[] NameList = new String[]{"小黄", "张三", "李四", "王五", "鹤叔", "丽丽", "小明", "阿杰", "媚姐", "王姨"};
 for (Integer amount : amountList) {
 System.out.println("搶到金額：" + new BigDecimal(amount).divide(new BigDecimal(100)) + "元");
 }
 }

 public static List<Integer> RedPackage(Integer TotalAmount, Integer TotalPeople) {
 List<Integer> amountList = new ArrayList<Integer>();
 Integer restAmount = TotalAmount;//剩餘金額
 Integer restPeople = TotalPeople;//剩餘人數
 Random random = new Random();
 for (int i = 0; i < TotalPeople - 1; i++) {
 //隨機範圍：[1,剩餘人均金額的兩倍]
 int amount = random.nextInt(restAmount / restPeople * 2 - 1) + 1;
 restAmount -= amount;
 restPeople--;
 amountList.add(amount);
 }
 amountList.add(restAmount);
 return amountList;
 }
}

有趣的抢红包算法

算法原理

代码展示

运行结果

猜你喜欢