Trouble with the While Statement

[Villanmac]

First up thanks to the guys who pointed out my error last week.

Now I was wondering If I could get some help with this problem because again I have fallen into trouble. Basically im using the while statement to loop a program but dont know how to loop back to the request of Enter hours worked or (-1 to end) : 39. I cant put it in the while statement as it contains the condition that activates the while statement, if you see what I mean?

Im trying to get a process like so

Sample screen input/ouput

Enter hours worked or (-1 to end) : 39
Enter hourly rate of worker (£00.00) : 10.00
Salary is £390.00

Enter hours worked or (-1 to end) : 40
Enter hourly rate of worker (£00.00) : 10.00
Salary is £400.00

Enter hours worked or (-1 to end) : 41
Enter hourly rate of worker (£00.00) : 10.00
Salary is £415.00

Enter hours worked or (-1 to end) : -1

But im getting this....

Enter hours worked or (-1 to end) : 39
Enter hourly rate of worker (£00.00) : 10.00
Salary is £390.00

Enter hourly rate of worker : 10.00
Salary is 390.00 (it uses my original value of hours and i dont know how to allow the user to input a new value of hours worked for a new worker.

Heres my program...

#include <iostream>
#include <cmath>
using std::cout;
using std::cin;
using std::endl;
 
 
int main ()
{
double hours;
double Pay_per_hour;
double Total_Pay;
 
cout << "Enter hours worked or -1 to end: ";
cin >> hours;
 
while (hours != -1)
{
   cout << "Enter hourly rate of the worker ";
   cin >> Pay_per_hour;
 
   if (hours <= 40)
      Total_Pay = hours * Pay_per_hour;
   else 
      Total_Pay = ( (hours - 40) * 15 ) + 400;
 
   cout << "Salary is  " << Total_Pay << endl;
 
}
 
 
return 0;
 
} // end main

[sicarie]

Your hours prompt and input need to be inside your while loop as well.

[mohammadazim]

You can move your prompt to hours in the loop and use a break statement to come out of loop. Like this...

//cout << "Enter hours worked or -1 to end: ";
//cin >> hours;
// move the above two inside the loop.
 
while (1) // make loop unconditional.
{
   cout << "Enter hours worked or -1 to end: ";
   cin >> hours;
//  ... and put a check for hours
   if (hours < 0)
      break;// break will take you out of loop.
   cout << "Enter hourly rate of the worker ";
   cin >> Pay_per_hour;
 
   if (hours <= 40)
      Total_Pay = hours * Pay_per_hour;
   else
      Total_Pay = ( (hours - 40) * 15 ) + 400;
 
   cout << "Salary is  " << Total_Pay << endl;
 
}
 
 

[Villanmac]

Your hours prompt and input need to be inside your while loop as well.

Thanks, but the problem I then have is when I click -1, the program does not terminate but still asks me the hourly rate of the worker and then works out his/her wage. When the user clicks -1 I want the program to terminate straight away but I cant do it.

[Villanmac]

You can move your prompt to hours in the loop and use a break statement to come out of loop. Like this...

//cout << "Enter hours worked or -1 to end: ";
//cin >> hours;
// move the above two inside the loop.
 
while (1) // make loop unconditional.
{
   cout << "Enter hours worked or -1 to end: ";
   cin >> hours;
//  ... and put a check for hours
   if (hours < 0)
      break;// break will take you out of loop.
   cout << "Enter hourly rate of the worker ";
   cin >> Pay_per_hour;
 
   if (hours <= 40)
      Total_Pay = hours * Pay_per_hour;
   else
      Total_Pay = ( (hours - 40) * 15 ) + 400;
 
   cout << "Salary is  " << Total_Pay << endl;
 
}
 
 

Cheers mohammad, that was what I was struggling with. Thanks again

I'd never come across the while(1) statement, so hadnt a chance