红包分配

public static double getRandomMoney(LeftMoneyPackage _leftMoneyPackage) {
    // remainSize 剩余的红包数量
    // remainMoney 剩余的钱
    if (_leftMoneyPackage.remainSize == 1) {
        _leftMoneyPackage.remainSize--;
        return (double) Math.round(_leftMoneyPackage.remainMoney * 100) / 100;
    }
    Random r     = new Random();
    double min   = 0.01; //
    double max   = _leftMoneyPackage.remainMoney / _leftMoneyPackage.remainSize * 2;
    double money = r.nextDouble() * max;
    money = money <= min ? 0.01: money;
    money = Math.floor(money * 100) / 100;
    _leftMoneyPackage.remainSize--;
    _leftMoneyPackage.remainMoney -= money;
    return money;
}