我有这个代码代表银行:classBank{friendclassInvestmentMethod;std::vectoraccounts;public://...BaseBankAccount是银行中所有账户的抽象类:classBaseBankAccount{public:BaseBankAccount(){}virtualintgetInterest()const=0;virtualintgetInvestedSum()const=0;virtualvoidincreaseDepositSum(intadditionalSum)=0;virtualvoidclose(std::str