text: //bank_account.h
  
  
  class BankAccount
  {
  
  public:
      BankAccount() : BankAccount(500){}
      BankAccount(int b) : balance{b} { bank balance }
      int get_balance() const {return balance;}
      void deposit(int amount);
      void withdraw(int amount);
      static int get_bank_balance(){return bank_balance;}
  private:
      int balance;
      static int bank_balance;
  };
  
  