每个人抢到的金额比较平均的算法
package com.example.demo.money; import java.math.BigDecimal; import java.util.ArrayList; import java.util.Collections; import java.util.List; import java.util.Random; public class SnatchMoney { //二倍均值法 public static List<Integer> divideRedPackage(Integer totalAmount, Integer totalPeopleNum) { List<Integer> amountList = new ArrayList<Integer>(); //为了使用random.nextInt(Integer)方法不得不先把红包金额放大100倍,最后在main函数里面再除以100 //这样就可以保证每个人抢到的金额都可以精确到小数点后两位 Integer restAmount = totalAmount * 100; Integer restPeopleNum = totalPeopleNum; Random random = new Random(); for (int i = 0; i < totalPeopleNum - 1; i++) { // 随机范围:[1,剩余人均金额的两倍),左闭右开 int amount = random.nextInt(restAmount / restPeopleNum * 2 - 1) + 1; restAmount -= amount; restPeopleNum--; amountList.add(amount); } amountList.add(restAmount); return amountList; } //随机金额法 private static List<Integer> divide(double money, int n) { //验证参数合理校验 //为了使用random.nextInt(Integer)方法不得不先把红包金额放大100倍,最后在main函数里面再除以100 //这样就可以保证每个人抢到的金额都可以精确到小数点后两位 int fen = (int) (money * 100); if (fen < n || n < 1) { System.out.println("红包个数必须大于0,并且最小红包不少于1分"); } List<Integer> boards = new ArrayList<>(); boards.add(0); boards.add(fen); //红包个数和板砖个数的关系 while (boards.size() <= n) { int index = new Random().nextInt(fen - 1) + 1; if (boards.contains(index)) { //保证板子的位置不相同- continue; } boards.add(index); } //计算每个红包的金额,将两个板子之间的钱加起来 Collections.sort(boards); List<Integer> list = new ArrayList<>(); for (int i = 0; i < boards.size() - 1; i++) { Integer e = boards.get(i + 1) - boards.get(i); list.add(e); } return list; } public static void main(String[] args) { // List<Integer> accountList = divideRedPackage(50, 1000); List<Integer> accountList = divideRedPackage(100, 10); BigDecimal count = new BigDecimal(0); for (Integer amount : accountList) { //将抢到的金额再除以100进行还原 BigDecimal tmpcount = new BigDecimal(amount).divide(new BigDecimal(100)); count = count.add(tmpcount); System.out.println("抢到金额:" + tmpcount); } System.out.println("total=" + count); } }