Sorting, Help!

[queenzgurl]

I'm going to get to the point. I am having problems understanding how to sort. Please explain how do I sort the netpay of the below code.
Thanks in advance!

#include<fstream>
#include<iostream>
#include<iomanip>

using namespace std;

//---------------------------------------------------------------------------\\ 
class payroll
{
    ifstream fin;
    int n;
    char employeename[20];
    int hoursworked,overtime;
    double hourlyrate,overtimepay,regularpay,grosspay,taxrate,taxamount,netpay;
    double totalnetpay,avgnetpay;
    
    void calculategrosspay();
    void calculatetax();
    void calculatenetpay();
    void findavgnetpay();
    void printheadings();
    void printdata();

public:
    payroll();
    ~payroll();
    void printreport(); 
};

//---------------------------------------------------------------------------\\ 
payroll::payroll()
{
      fin.open("payrollclass.txt"); 
}

//---------------------------------------------------------------------------\\       
payroll::~payroll()
{
      fin.close(); 
}

//---------------------------------------------------------------------------\\   
void payroll::calculategrosspay()
{
    if(hoursworked > 40)
    {
        overtime = hoursworked - 40;
        regularpay = hoursworked * hourlyrate;
        overtimepay = overtime * (hourlyrate * 1.5);
        grosspay = regularpay + overtimepay; 
    }
    else
    { 
        grosspay = hoursworked * hourlyrate; 
        regularpay = grosspay; 
        overtimepay = 0;
    }
}

//---------------------------------------------------------------------------\\ 
void payroll::calculatetax()
{
       taxrate = .30;
       taxamount = grosspay * taxrate; 
}

//---------------------------------------------------------------------------\\ 
void payroll::calculatenetpay()
{
    netpay = grosspay - taxamount;
    totalnetpay = totalnetpay + netpay;
}

//---------------------------------------------------------------------------\\ 
void payroll::findavgnetpay()
{
   avgnetpay = totalnetpay / n;
}   

//---------------------------------------------------------------------------\\ 
void payroll::printheadings()
{
    cout << setw(40)<<"-Dr. Ebrahimi Payroll Institute-"<<endl;
    cout << "---------------------------------------------------------" << endl;
    cout << " NAME     HW     HR     OT-PAY  GROSS   TAX   NETPAY"   << endl;
    cout << "---------------------------------------------------------" << endl;
}

//---------------------------------------------------------------------------\\ 
void payroll::printdata()
{
    cout << setprecision(2) << setiosflags(ios::fixed|ios::showpoint);
    cout << setw(6) << employeename << setw(6) << hoursworked << setw(8) <<
            hourlyrate << setw(8) << overtimepay << setw(8) << grosspay <<
            setw(8) << taxamount << setw(8) << netpay << endl; 
}

//---------------------------------------------------------------------------\\ 
void payroll::printreport()
{
    n = 0; 
    totalnetpay = 0;
    printheadings();
    while(fin >> employeename >> hoursworked >> hourlyrate)
    {
        calculategrosspay();
        calculatetax();
        calculatenetpay();
        printdata();
        n++; 
    }

    findavgnetpay();
    cout << endl << "The average net pay for " << n << " employees is " << avgnetpay << endl;

}
          
//---------------------------------------------------------------------------\\ 
int main()
{
    payroll employee;
    employee.printreport();
    system ("pause");
} 
//---------------------------------------------------------------------------\\  

[hamsterman]

Well, you can't sort them if you don't store them anywhere..
Generally, your structure is a bit wrong. "payroll" is at the same time a single employee (since it has name, hours worked, etc) and the whole group (since it has n, totalnetpay, etc).
You should split it in two:

struct employee{
    char employeename[20];
    int hoursworked,overtime;
    double hourlyrate,overtimepay,regularpay,grosspay,taxrate,taxamount,netpay;

    void calculategrosspay();
    void calculatetax();
    void calculatenetpay();
    void printdata();
};

and

struct workplace{
    std::vector<employee> workers;//this could be "employee workers[big_number]; int n;" if you don't know vectors
    double totalnetpay, avgnetpay;
    
    void readdata();
    void sortdata();
    void printheadings();
    void printreport();
};

Something like that anyway..