بإستخدام لغة ال c++ , اكتب صف class يمثل حساب مصرفي Account ؟

#include <iostream>
using namespace std;
class Account{
    const long id_;
    long balance;
public:
    Account(long id):id_(id){}
    Account& operator+=(int val){
        balance += val;
        return *this;
    }
    friend bool operator==(Account&, Account&);
    void setBalance(long b){
        balance = b;
    }
};
bool operator== (Account& a, Account& b){
  if (a.balance == b.balance)
    return true;
  else return false;
}
int main(){
    Account a1(111111);
    Account a2(222222);
    a1.setBalance(600);
    a2.setBalance(600);
    a1+=20;
    if (a1== a2)
        cout << "a1 is equal to a2";
    else
        cout << "a1 is not equal to a2";
return 0;
}