许久未碰java，写的有点拙。
package com.cjh.test;import java.util.ArrayList;import java.util.Arrays;import parator;import java.util.Random;/*** * @author chenjiahui* @-02-09**/public class Test {public static void main(String[] args) {splitRedPacket(40000, 41, 300, 1500);System.out.println("*****************");splitRedPacket(20000, 30, 300, 1000);}/*** * @param total* 总金额* @param splitCount* 个数* @param min* 最小金额* @param max* 最大金额*/public static void splitRedPacket(int total, int splitCount, int min, int max) {System.out.println("总金额：" + total);System.out.println("个数：" + splitCount);System.out.println("最小金额：" + min);System.out.println("最大金额：" + max);ArrayList<Integer> al = new ArrayList<Integer>();Random random = new Random();if ((splitCount & 1) == 1) {// 奇数个红包，需要单独将其中一个红包先生成，以保证后续算法拆分份数为偶数。System.out.println("红包个数" + splitCount + "是奇数，单独生成一个红包");int num = 0;do {num = random.nextInt(max);// num = (total - num) % (splitCount / 2) + num; //// 将后面算法拆分时的余数加入到这个随机值中。System.out.println("单个的随机红包为：" + num);} while (num >= max || num <= min);total = 40000 - num;al.add(num);}int couples = splitCount >> 1;int perCoupleSum = total / couples;if ((splitCount & 1) == 1) {System.out.println("处理后剩余的金额为：" + total);}System.out.println("将" + total + "元拆分为" + couples + "对金额，每对总额：" + perCoupleSum);for (int i = 0; i < couples; i++) {Boolean finish = true;int num1 = 0;int num2 = 0;do {num1 = random.nextInt(max);num2 = perCoupleSum - num1;if (!al.contains(num1) && !al.contains(num2)) {if (i == 0) {num1 = (total - couples * perCoupleSum) + num1;}}} while (num1 < min || num1 > max || num2 < min || num2 > max);al.add(num1);al.add(num2);}int check_num = 0;pare(1, 2);al.sort(new Comparator<Integer>() {@Overridepublic int compare(Integer o1, Integer o2) {return pare(o1, o2);}});System.out.println(Arrays.toString(al.toArray()));for (int x : al) {check_num = check_num + x;}System.out.println("验证总和：" + check_num);}}
