Erklärung gekündigt Falsch Fehler in folgenden code in cpp

Iam, der versucht, sich zu entwickeln C++ - Programm für observer-Muster, aber ich bin immer diese Fehler.
Hier ist meine CPP-code , und ich immer Fehler ständig : "Erklärung der Kündigung falsch" !
Vielen Dank im Voraus
Helfen Sie mir bitte ich bin verzweifelt.

#include<iostream.h>
#include<stdio.h>
#include<conio.h>

class Subject{
public :        virtual ~Subject();
        virtual float attach()=0;
        virtual int notify()=0;
};

class Observer{
public :        virtual ~Observer();
        virtual void update(int type, float amount, float bal)=0;
};

class Account : public Subject
{
public:  float attach()
 {
    char name[12];
    int account_no;
    float bal;
    cout<<"Enter the Name of Account Holder : ";
    cin>>name;
    cout<<"Enter the Account No. : ";
    cin>>account_no;
    cout<<"Enter the Balance of his account : ";
    cin>>bal;
    cout<<"The Name of Account Holder : "<<name;
    cout<<"The Account No. : "<<account_no;
    cout<<"The Balance of his account : "<<bal;
    return bal;
}
int notify()
{
    int type;
    cout<<"\nMenu :\n\n1) Deposit\n2)Withdrawl\n";
    cout<<"Enter the type  for transition : \n";
    cin>>type;
    return type;
}
public: void update(int type, float amount, float bal)
{
    char name[12];
    int account_no;
    if(type==1)
        bal=bal+amount;
    else if(type==2)
        bal=bal-amount;
    else
        cout<<"Oops! Transition Type is invalild....";
    cout<<"\nThe Details of Account Holder after Transition     :-\n";
    cout<<"The Name of Account Holder : "<<name;
    cout<<"The Account No. : "<<account_no;
    cout<<"The Balance of his account : "<<bal;
}
};

class obpt{
public : static void main()
{
    Account ac;
    //AccountUpdate au;
    float balance, amt;
    int type;
    clrscr();
    cout<<"\nWelcome To The Program of Observer Pattern of Account Transition\n";
    cout<<"\nEnter the Details of Account Holder :-\n";
    balance = ac.attach();
    cout<<"\nCall notification for Deposit or Withdrawl Transition\n";
    type=ac.notify();
    cout<<"\nEnter the amount for transition : \n";
    cin>>amt;
    cout<<"\nAfter The transition the Main balance : \n";
    ac.update(type, amt, balance);
    getch();
}
}