Banking Problem

[ashu]

hi to all,
Please read the following ques. first.

assume that a bank maintains 2 kinds of accounts for
customers one called as
savings accounts & other as current account.
the savings account provides simple interest &
withdraw facilities but no check book facilities.
the current account provides check book facilities but
no interest.
current account holders should also maintain a minimum
balance and if the minimum balance falls below this
level a service charge is to be imposed.

create a class account that stores customers name,
account no & type of account
from this class derive the classes current acc &
savings acc. to make them more
specific to their environments. include necessary
member functions in order to achieve following tasks:
1. accept the deposit from the customer and compute
the balance
2. display the balance
3. compute and deposit the interest
4. permit the withdrawl and update the balance
5. check the minimun balance, impose penalty if
necessary &update the balance

-->>DO NOT USE CONSTRUCTORS AND USE MEMBER FUNCTIONS
TO INITIALIZE THE CLASS MEMBERS

(NOTE: #MAKE AN EXTRA FIELD DATE (INCLUDE DOS.H TO
ACCESS DATE STRUCTURE)
#MAKE THIS PROGRAM BY USING LINK LIST )


The problem i am facing is that when i have created two derived class
as directed, i have to create two linklist to each derived class. So at
the time of modifing, depositing or any other operation, i have to
search both the linklist, which will be very time consuming & if no
such account exist, it would be the worst of the worst case. Then i
think another solution, i make another derived class by taking (saving
& current class) early derived class as base class & create a single
linklist. Now, the problem in that is, when my account is saving type,
my current class in totally untouched(wasted) & vice-versa.
I want to make a single linklist by merging two linklist. Would anyone
suggest me the solution. The program should be Menu Driven.

Thank You

 

[mlimber]

hi to all,
Please read the following ques. first.

assume that a bank maintains 2 kinds of accounts for
customers one called as
savings accounts & other as current account.
the savings account provides simple interest &
withdraw facilities but no check book facilities.
the current account provides check book facilities but
no interest.
current account holders should also maintain a minimum
balance and if the minimum balance falls below this
level a service charge is to be imposed.

create a class account that stores customers name,
account no & type of account
from this class derive the classes current acc &
savings acc. to make them more
specific to their environments. include necessary
member functions in order to achieve following tasks:
1. accept the deposit from the customer and compute
the balance
2. display the balance
3. compute and deposit the interest
4. permit the withdrawl and update the balance
5. check the minimun balance, impose penalty if
necessary &update the balance

-->>DO NOT USE CONSTRUCTORS AND USE MEMBER FUNCTIONS
TO INITIALIZE THE CLASS MEMBERS

(NOTE: #MAKE AN EXTRA FIELD DATE (INCLUDE DOS.H TO
ACCESS DATE STRUCTURE)
#MAKE THIS PROGRAM BY USING LINK LIST )


The problem i am facing is that when i have created two derived class
as directed, i have to create two linklist to each derived class. So at
the time of modifing, depositing or any other operation, i have to
search both the linklist, which will be very time consuming & if no
such account exist, it would be the worst of the worst case. Then i
think another solution, i make another derived class by taking (saving
& current class) early derived class as base class & create a single
linklist. Now, the problem in that is, when my account is saving type,
my current class in totally untouched(wasted) & vice-versa.
I want to make a single linklist by merging two linklist. Would anyone
suggest me the solution. The program should be Menu Driven.

Thank You

See this FAQ:

http://www.parashift.com/c++-faq-lite/how-to-post.html#faq-5.2

This newsgroup is for C++ language questions. If you have a specific
language-related question, we will be happy to help you. Otherwise, you
might want to try in comp.programming or
comp.please.do.my.homework.for.me.

Cheer! --M

 

[Kai-Uwe Bux]

ashu wrote: [snip]

The problem i am facing is that when i have created two derived class
as directed, i have to create two linklist to each derived class. So at
the time of modifing, depositing or any other operation, i have to
search both the linklist, which will be very time consuming & if no
such account exist, it would be the worst of the worst case. Then i
think another solution, i make another derived class by taking (saving
& current class) early derived class as base class & create a single
linklist. Now, the problem in that is, when my account is saving type,
my current class in totally untouched(wasted) & vice-versa.
I want to make a single linklist by merging two linklist. Would anyone
suggest me the solution. The program should be Menu Driven.

[snip]
This newsgroup is for C++ language questions. If you have a specific
language-related question, we will be happy to help you. Otherwise, you
might want to try in comp.programming or
comp.please.do.my.homework.for.me.

Don't be so eager to dismiss this as off topic. Actually, there is a
language question in there: given two classes, deriving from a common base,
does C++ have a mechanism to have objects of both types in the same
container. If so, what is the recommended was to go about it?

And a possible answer is: you can use a container of pointers to the base
class. Better even, use a container of reference counting smart_pointers to
the base class so that memory management is still automatic.

To the OP: this should get you started. Post again when you have a draft of
your code and you are running into more serious problems. Also, please do
not roll your own code for the linked list. Use std::list<> instead. It
will save you serious headache.


Best

Kai-Uwe Bux

 

[ashu]

Thank you for considering my problem & guiding me so well. As i'm new
to the Oops, i not know much about Oops. So would you please tell me
what are containers of pointers, container of reference counting
smart_pointers???.

And "please do not roll your own code for the linked list. Use
std::list<> instead" ????? what does this line means. please tell me.

 

[Kristo]

Thank you for considering my problem & guiding me so well. As i'm new
to the Oops, i not know much about Oops. So would you please tell me
what are containers of pointers, container of reference counting
smart_pointers???.

Rather than have one of us explain it, I suggest picking up a good C++
book (or two) and reading it. IIRC, the FAQ has several good
recommendations.

And "please do not roll your own code for the linked list. Use
std::list<> instead" ????? what does this line means. please tell me.

It means that you should use the list class provided by the Standard
Library instead of writing your own.

Kristo

 

[osmium]

assume that a bank maintains 2 kinds of accounts for
customers one called as
savings accounts & other as current account.
the savings account provides simple interest &
withdraw facilities but no check book facilities.
the current account provides check book facilities but
no interest.
current account holders should also maintain a minimum
balance and if the minimum balance falls below this
level a service charge is to be imposed.

create a class account that stores customers name,
account no & type of account
from this class derive the classes current acc &
savings acc. to make them more
specific to their environments. include necessary
member functions in order to achieve following tasks:
1. accept the deposit from the customer and compute
the balance
2. display the balance
3. compute and deposit the interest
4. permit the withdrawl and update the balance
5. check the minimun balance, impose penalty if
necessary &update the balance

-->>DO NOT USE CONSTRUCTORS AND USE MEMBER FUNCTIONS
TO INITIALIZE THE CLASS MEMBERS

(NOTE: #MAKE AN EXTRA FIELD DATE (INCLUDE DOS.H TO
ACCESS DATE STRUCTURE)
#MAKE THIS PROGRAM BY USING LINK LIST )


The problem i am facing is that when i have created two derived class
as directed, i have to create two linklist to each derived class. So at
the time of modifing, depositing or any other operation, i have to
search both the linklist, which will be very time consuming & if no
such account exist, it would be the worst of the worst case. Then i
think another solution, i make another derived class by taking (saving
& current class) early derived class as base class & create a single
linklist. Now, the problem in that is, when my account is saving type,
my current class in totally untouched(wasted) & vice-versa.
I want to make a single linklist by merging two linklist. Would anyone
suggest me the solution. The program should be Menu Driven.

First of all, a linked list is a very bad data structure for this problem,
it will be terribly slow and no reasonable amount of cleverness is going to
change that. That *might* be the point your instructor is trying to make.
He specifies you are not to use a meaningful constructor, and this is a
prelude to an obvious array solution, using hashing. Then, for a subsequent
assignment he has you already motivated for a better data structure.

I don't really understand everything you said, I suspect there is an English
problem. You seem to focus on the worst case, a customer who claims to have
an account in fact doesn't have one. Are you proposing three lists? And
some way to get the "customer" to answer some question or other truthfully?

 

[Karl Heinz Buchegger]

That *might* be the point your instructor is trying to make.

I think the point his instructor is trying to make is an exercise
on how to use a polymorphic class in a container (plus an exercise
in constructing a linked list, if he has to code the list by hand).

Never forget: This are class room assignments, not real world
applications.

 

[Jim Langston]

The problem i am facing is that when i have created two derived class
as directed, i have to create two linklist to each derived class. So at
the time of modifing, depositing or any other operation, i have to
search both the linklist, which will be very time consuming & if no
such account exist, it would be the worst of the worst case. Then i
think another solution, i make another derived class by taking (saving
& current class) early derived class as base class & create a single
linklist. Now, the problem in that is, when my account is saving type,
my current class in totally untouched(wasted) & vice-versa.
I want to make a single linklist by merging two linklist. Would anyone
suggest me the solution. The program should be Menu Driven.

Maybe this will get you started:

class Base
{
public:
virtual ~Base() {};
};

class Derived1 : Base
{
public:
~Derived1(){};
};

class Derived2 : Base
{
public:
~Derived2 () {};
};

int main()
{
Base* baseP1;
Base* baseP2;
baseP2 = new Derived1;
baseP2 = new Derived2;
};

What I'm showing here is that a base pointer can point to a derived object.
So a linked list of base objects can point to any derived objects of base.

Read your textbook on this.

 

[ashu]

here, the object of base class can't access the member data & functions
of derived class, as inheritance not work in opposite direction, so
can't help.

 

[Karl Heinz Buchegger]

here, the object of base class can't access the member data & functions
of derived class, as inheritance not work in opposite direction, so
can't help.

Right. But the base class should not access all of this.

All your base class needs to do is:
make available a couple of virtual functions, which are
implemented in the derived classes.

Eg. The base class introduces functions for handling
of check books. In the 'current account' class, these
functions are fully implemented, while in the 'savings account'
class they are do-nothing-functions (or not implemented at all).

Virtual functions, paired with inheritance is the key to your
assignment!

 

[Jim Langston]

here, the object of base class can't access the member data & functions
of derived class, as inheritance not work in opposite direction, so
can't help.

Actually, it can. Here is a working program showing how using Run Time Type
Checking (RTTI). Polymorphism would be worthless otherwise.

#include <vector>
#include <iostream>
class Base
{
public:
virtual ~Base() {};
virtual void CommonFunc() = 0;
};

class Derived1 : Base
{
public:
~Derived1(){};
void D1Func() { std::cout << "Derived1" << std::endl; };
void CommonFunc() { std::cout << "Derived1 Common" << std::endl; };
};

class Derived2 : Base
{
public:
~Derived2 () {};
void D2Func() { std::cout << "Derived2" << std::endl; };
void CommonFunc() { std::cout << "Derived2 Common" << std::endl; };
};

int main()
{
std::vector<Base*> MyVector;
MyVector.push_back( (Base*) new Derived1 );
MyVector.push_back( (Base*) new Derived2 );
std::vector<Base*>::iterator it;
for ( it = MyVector.begin(); it != MyVector.end(); ++it )
{
if ( dynamic_cast<Derived1*> (*it) != NULL )
dynamic_cast<Derived1*>(*it)->D1Func();
if ( dynamic_cast<Derived2*> (*it) != NULL )
dynamic_cast<Derived2*>(*it)->D2Func();
(*it)->CommonFunc();
}
char wait;
std::cin >> wait;
};

Output is:
Derived1
Derived1 Common
Derived2
Derived2 Common

 

[Jim Langston]

Actually, it can. Here is a working program showing how using Run Time
Type Checking (RTTI). Polymorphism would be worthless otherwise.

In addition to what I showed you, you should note that the
(*it).CommonFunc() didn't need to dynamic cast the object, because it would
call the function for whichever object was instatized since it was contained
in the base.

Basically you only have to do a dynamic_cast if you want to call a method
that only exists in a derived object, not the base. If the method exists in
the base just call it and it will use the derived's overriden method (if
there is one).

So if you didn't to use dynamic_casts you could enter "stubs" for all
methods that simply do nothing. Such as:

class Account
{
public:
virtual void CalcInterest() { }; // Default is do nothing
};

class Savings: Account
{
void CalcInterest() { Balace += Balance * 0.014; };
};

class Checking: Account
{
// Checking doesn't override CalcInterest()
};

So now when call:
(*it)->CalcInterest();

if the actual instance is Savings, nothing will happen as the base method
will be used which does nothing. If the instance is Checking the Balance
will be updated. Not dynamic_cast needed since the method CalcInterest()
exists in the base class.

 

[mlimber]

Actually, it can. Here is a working program showing how using Run Time Type
Checking (RTTI). Polymorphism would be worthless otherwise.

I wouldn't say worthless. In fact, in my current project I use
polymorphism extensively but have RTTI disabled via a compiler switch
because my classes follow the more standard method of design described
by Karl above and don't need it.

#include <vector>
#include <iostream>
class Base
{
public:
virtual ~Base() {};
virtual void CommonFunc() = 0;
};

class Derived1 : Base
{
public:
~Derived1(){};
void D1Func() { std::cout << "Derived1" << std::endl; };
void CommonFunc() { std::cout << "Derived1 Common" << std::endl; };
};

class Derived2 : Base
{
public:
~Derived2 () {};
void D2Func() { std::cout << "Derived2" << std::endl; };
void CommonFunc() { std::cout << "Derived2 Common" << std::endl; };
};

int main()
{
std::vector<Base*> MyVector;
MyVector.push_back( (Base*) new Derived1 );
MyVector.push_back( (Base*) new Derived2 );
std::vector<Base*>::iterator it;
for ( it = MyVector.begin(); it != MyVector.end(); ++it )
{
if ( dynamic_cast<Derived1*> (*it) != NULL )
dynamic_cast<Derived1*>(*it)->D1Func();

Better would be:

if( Derived1* p = dynamic_cast<Derived1*>(*it) )
{
p->D1Func();
}

Then, at least there's only one call to the non-trivial dynamic_cast.

if ( dynamic_cast<Derived2*> (*it) != NULL )
dynamic_cast<Derived2*>(*it)->D2Func();
(*it)->CommonFunc();
}
char wait;
std::cin >> wait;
};

Output is:
Derived1
Derived1 Common
Derived2
Derived2 Common

Cheers! --M

 

[Jim Langston]

I wouldn't say worthless. In fact, in my current project I use
polymorphism extensively but have RTTI disabled via a compiler switch
because my classes follow the more standard method of design described
by Karl above and don't need it.

Actually, my "Polymorphism would be worthless otherwise" was refering to the
fact that the member data & functions can be assess through a base pointer,
not to RTII. I had added the last sentance as an afterthough. Switch
sentances 2 and 3 around and it what I meant to say (IOW, I agree with
you)

Better would be:

if( Derived1* p = dynamic_cast<Derived1*>(*it) )
{
p->D1Func();
}

Then, at least there's only one call to the non-trivial dynamic_cast.

Agreed.