I recently finished some C++ practices from my teacher and he told me my answers got a classic issues.
I'm pretty new and I really can't figure it out, so, give me a hand please. Thanks.
Here is the question:
Describe the bad design of the following codes and redesign the classes.
class Customer
{
public:
int birthYear;
bool isCurrentMember;
int numberOfPurchases;
Customer()
{
// Test data.
birthYear = 1963;
isCurrentMember = false;
numberOfPurchases = 33;
}
void DisplayDetails()
{
printf( "Birth Year: %ld\r\n", birthYear );
printf( "Current Member: %s\r\n", isCurrentMember ? "Yes" : "No" );
printf( "Number Of Purchases: %ld\r\n\r\n", numberOfPurchases );
}
};
class Salesman
{
private:
Customer bestCustomer;
Customer worstCustomer;
public:
int id;
Salesman( int initialID )
{
id = initialID;
}
Customer BestCustomer()
{
return bestCustomer;
}
Customer* WorstCustomer()
{
return &worstCustomer;
}
};
class SalesTeam
{
public:
Salesman salesman1;
Salesman salesman2;
SalesTeam()
: salesman1(1000), salesman2(1001)
{}
void DisplayTeam()
{
printf( "Salesman 1: %ld\r\n", salesman1.id );
printf( "Salesman 2: %ld\r\n", salesman2.id );
}
};
void TestSalesmanCustomers()
{
SalesTeam ourTeam;
int medianSales_1 =
(ourTeam.salesman1.BestCustomer().numberOfPurchases
+ ourTeam.salesman1.WorstCustomer()->numberOfPurchases) / 2;
int medianSales_2 =
(ourTeam.salesman2.BestCustomer().numberOfPurchases
+ ourTeam.salesman2.WorstCustomer()->numberOfPurchases) / 2;
printf( "Salesman median sales = %ld\r\n", medianSales_1);
printf( "Salesman median sales = %ld\r\n", medianSales_2);
}
And here is my answer
Header:
#ifndef _REDESIGN_H
#define _REDESIGN_H
#include <stdio.h>
#include <list>
// Customer class
// *In the future this class should provide functions to set
// m_birthYear, m_isCurrentMember and m_numberOfPurchases values
// in case of changes.
class Customer
{
public:
Customer( int birthYear, bool isMember, int numOfPurchases ):
m_birthYear(birthYear),
m_isCurrentMember(isMember),
m_numberOfPurhchases(numOfPurchases) {}
~Customer() {}
// functions to get private member variables
int getBirthYear() { return m_birthYear; }
int getNumOfPurchases() { return m_numberOfPurhchases; }
bool checkCurrentMember() { return m_isCurrentMember; }
void displayDetails();
private:
int m_birthYear;
bool m_isCurrentMember;
int m_numberOfPurhchases;
};
// Salesman class
// *In the future, function to search customers by their birthYear, NumberOfPurchases and
// memberStats could be added.
// *Comparison in function addCustomer() could be extended to consider more
// situations include membership status.
class Salesman
{
public:
Salesman( int initialID );
~Salesman() { m_customerList.clear(); }
Customer* getBestCustomer() { return m_bestCustomer; }
Customer* getWorstCustomer() { return m_worstCustomer; }
bool addCustomer( Customer* cust )
int getID();
private:
Customer* m_bestCustomer;
Customer* m_worstCustomer;
int m_id;
// Container to store list of customer pointers
std::list<Customer*> m_customerList;
bool m_firstTime;
};
// SalesTeam class
// *Function to remove a salesman from saleteam by id could be implemented
// in the future.
// *Function to calculte particular salesman's median sales nunmber can be implemented
class SalesTeam
{
public:
SalesTeam() {}
~SalesTeam() { m_salesmanList.clear(); }
bool addSalesman( Salesman* sales );
Salesman* getSalesman( int id );
void displayTeam();
private:
// *Container to store list of salesman pointers.
// *Makes the class more flexible and easier to
// handle.
std::list<Salesman*> m_salesmanList;
};
#endif CPP:
#include "Redesign.h"
//--------------------------------------------------------------------
// Customer class implementations
void Customer::displayDetails()
{
printf( "Birth Year: %ld\r\n", m_birthYear );
printf( "Current Member: %s\r\n", m_isCurrentMember ? "Yes" : "No" );
printf( "Number Of Purchases: %ld\r\n\r\n", m_numberOfPurhchases );
}
//-------------------------------------------------------------------
// Salesman class implementations
Salesman::Salesman( int initialID )
{
m_id = initialID;
m_firstTime = true;
m_bestCustomer = 0;
m_worstCustomer = 0;
}
int Salesman::getID()
{
return m_id;
}
bool Salesman::addCustomer( Customer* cust )
{
// Finds out best and worst customer by comparing their
// number of purchases
if( cust )
{
// First time initials
if( m_firstTime )
{
m_bestCustomer = cust;
m_worstCustomer = cust;
m_firstTime = false;
}
m_customerList.push_back( cust );
// comparison
if( cust->getNumOfPurchases() >= m_bestCustomer->getNumOfPurchases() )
m_bestCustomer = cust;
else if( cust->getNumOfPurchases() <= m_worstCustomer->getNumOfPurchases() )
m_worstCustomer = cust;
return true;
}
else return false;
}
//------------------------------------------------------------------
// SalesTeam class implementation
bool SalesTeam::addSalesman( Salesman* sales )
{
// Check if pointer valid
if( sales )
{
m_salesmanList.push_back( sales );
return true;
}
else return false;
}
Salesman* SalesTeam::getSalesman( int id )
{
auto it = m_salesmanList.begin();
while( it != m_salesmanList.end() )
{
if( (*it)->getID() == id )
return (*it);
++it;
}
return 0;
}
void SalesTeam::displayTeam()
{
auto it = m_salesmanList.begin();
while( it != m_salesmanList.end() )
{
printf( "Salesman: %ld\r\n", (*it)->getID() );
++it;
}
}
Thank you guys
