Ｓｏｒｒｙ 又來求救了 程式功能： 把Ｓｉｍ＿０１的部分錢轉到Ｓｉｍ＿０２ 還要check錢夠不夠傳！ 懇請各位先進賜教！！ =========== 錯誤訊息： [Linker Error] Unresolved external 'BankAccount::save' referenced from C:\C \test.OBJ [Linker Error] Unresolved external 'BankAccount::yn' referenced from C:\C \test.OBJ 我看不出我哪裡有錯阿！！ =========== 程式內容

#include     using std::cout;    using std::cin;    using std::endl;        class BankAccount{        private:            char* name;            int saving;        public:            static int save;
        static int yn;            BankAccount(char* str, int money){                name = str;
            saving = money;
            save=saving;            }            void deposit(int money){                saving  = money;            }            int withdraw(int money){                saving -= money;                return saving;            }            void query(){                cout << "帳戶姓名：" << name << endl;                cout << "帳戶餘額：" << saving << endl;            }    };    class ExBankAccount : public BankAccount{        public:            ExBankAccount(char* str, int money):BankAccount(str, money){            }            void transfer(BankAccount *A, int money)
        {
                if(yn==1)
                {
                withdraw(money);
                A->deposit(money);
                }
        }
};    class EExBankAccount : public ExBankAccount{        public:            EExBankAccount(char* str, int money):ExBankAccount(str, money){            }            void check(BankAccount A, int money)
        {
                if(save>=money)
                {
                        yn=1;
                }
                else
                {
                        yn=0;
                }
        }    };    void main()    {
    int I,J,M;
    cout << "Insert a money for Sim_01, please ：" ;
    cin >> J;
    cout << "Insert a money for Sim_02, please ：" ;
    cin >> M;
    cout << "Insert a number of transfer, please ：" ;
    cin >> I;
    EExBankAccount Sim_01("Sim_01", J);        EExBankAccount Sim_02("Sim_02", M);        Sim_01.check (Sim_02, I);
    Sim_01.transfer (&Sim_02, I);        Sim_01.query();        Sim_02.query();    }

Frances3399您好 問題便是出在基礎類別BankAccount的成員static int save與static int yn, 在類別內宣告static則在物件產生之前已配置記憶體,也就是說他們不屬於個別 物件所有,而是物件共用的... 而這二個變數主要是Sim_01用來判斷轉出的錢是否合理...因此不需static, 只要在物件生成時再產生就可以了...     

 類別宣告
class BankAccount{        private:            char* name;            int saving;        public:            int save;//去掉static
        int yn;//去掉static            BankAccount(char* str, int money){                name = str;
            saving = money;
            save=saving;            }            void deposit(int money){                saving  = money;            }            int withdraw(int money){                saving -= money;                return saving;            }            void query(){                cout << "帳戶姓名：" << name << endl;                cout << "帳戶餘額：" << saving << endl;            }    };

程式迷人之處,在於邏輯思考,然而卻也是惱人之處~~

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程式迷人之處,在於邏輯思考,然而卻也是惱人之處~~

由衷感謝各位先進幫忙！！ 謝謝！！