Looping assignment in C++ - c++

Question

My assignment is utilizing loops. The program should accept input for the sales of 3 employees (Mary, Tom, and Chris). The flow should be as follows:
Initial? > number of sales to enter > enter sale amounts > display commission for sale at 17% > adds commission and sales to the respective variables >> continue until 'z' is input for inputSalesPerson >> display information
So I am trying to figure out why my return value for the tempComm variable isn't returning the correct value. If i was to enter 't' for variable inputSalesPerson it puts me into the switch case 't' no problem. Input number of sales and that works. But when I get to entering the salesAmount and then displaying commission it will not calculate correctly.
Also if I enter 'z' or 'Z' as the inputSalesPerson it will not end the program. I have a lot to go on this.
#include <iomanip>
#include <iostream>
using namespace std;
int main()
{
int salesT = 0, salesC = 0, salesM = 0;
double amountT = 0, amountC = 0, amountM = 0;
double commT = 0, commC = 0, commM = 0;
double commRate = (17/100);
int num_sales;
double salesAmount, totalSales, tempComm;
char inputSalesPerson;
do
{
cout << "Enter the sales person's initial (\"Z\" to quit): ";
cin >> inputSalesPerson;
while(inputSalesPerson != 't' && inputSalesPerson != 'T' && inputSalesPerson != 'm' && inputSalesPerson != 'M' && inputSalesPerson != 'c' && inputSalesPerson != 'C' && inputSalesPerson != 'z' && inputSalesPerson != 'Z')
{
cin.get();
system("cls");
cout << "Invalid input for employee. Please Input (T)om, (C)hris, (M)ary, or (Z) to End : ";
cin >> inputSalesPerson;
}
switch(inputSalesPerson)
{
case 't' :
case 'T' :
system("cls");
cout << "Enter the number of sales : ";
cin >> num_sales;
while(num_sales < 1 || num_sales > 5)
{
system("cls");
cout << "Invalid number of sales. Please enter a value between 1 and 5 : ";
cin >> num_sales;
}
salesT += num_sales;
for(int i = 0; i<num_sales; i++)
{
cin.get();
system("cls");
cout << "Enter the sale amount : ";
cin >> salesAmount;
while(salesAmount < 0)
{
cin.get();
system("cls");
cout << "Invalid sale amount. Please enter a positive amount : ";
cin >> salesAmount;
}
tempComm = salesAmount + (salesAmount * commRate);
cout << fixed << setprecision(2) << "Commission earned by tom on this sale is : " << tempComm << endl;
cin.get();
amountT += salesAmount + tempComm;
commT += tempComm;
totalSales += amountT;
}
break;
}
}while(inputSalesPerson != 'z' || 'Z');
return 0;
}
****EDIT****
Thank you for the information on single-step debugging. Thanks to that comment I was able to learn about using the debugging tool more in depth and that helped me get everything working a bit better.

Answer 1

I've commented your code at the areas that need fixing. Also, there's a problem with using cin.get() all over the place. I assume that you do this to discard the return character after each input. But if the standard input (cin) is empty when you call cin.get() it will block the program until something is input. This is what happens when you enter more than one num_sales:
for (int i = 0; i<num_sales; i++)
{
cin.get();
It handles the first fine, but on the second loop you get:
Enter the sale amount : 20
Commission earned by tom on this sale is : 23.40
// cin.get() blocks here, with no user instructions to enter the next sale amount
I've commented out all the cin.get(). It will still work the same because the cin operator >> discards whitespaces and newlines, so even if there is a \n newline character still in the buffer, the next time you do something like cin >> num_sales it will discard the newline anyway.
#include <iomanip>
#include <iostream>
using namespace std;
int main()
{
int salesT = 0, salesC = 0, salesM = 0;
double amountT = 0, amountC = 0, amountM = 0;
double commT = 0, commC = 0, commM = 0;
double commRate = (17 / 100.0); // Int divided by int will round to an int.
// commRate is 0.0. Divide by double instead (17 / 100.0)
int num_sales;
double salesAmount, totalSales = 0, tempComm; // totalSales needs to be initialised to
// zero, otherwise it holds a garbage value.
char inputSalesPerson;
do
{
cout << "Enter the sales person's initial (\"Z\" to quit): ";
cin >> inputSalesPerson;
while (inputSalesPerson != 't' && inputSalesPerson != 'T' && inputSalesPerson != 'm' && inputSalesPerson != 'M' && inputSalesPerson != 'c' && inputSalesPerson != 'C' && inputSalesPerson != 'z' && inputSalesPerson != 'Z')
{
//cin.get();
system("cls");
cout << "Invalid input for employee. Please Input (T)om, (C)hris, (M)ary, or (Z) to End : ";
cin >> inputSalesPerson;
}
switch (inputSalesPerson)
{
case 't':
case 'T':
system("cls");
cout << "Enter the number of sales : ";
cin >> num_sales;
while (num_sales < 1 || num_sales > 5)
{
system("cls");
cout << "Invalid number of sales. Please enter a value between 1 and 5 : ";
cin >> num_sales;
}
salesT += num_sales;
for (int i = 0; i<num_sales; i++)
{
//cin.get();
//system("cls");
cout << "Enter the amount for sale number " << i+1 << ": ";
cin >> salesAmount;
system("cls"); // I would put the clear here,
// Otherwise the user can't see the commission made by Tom
while (salesAmount < 0)
{
//cin.get();
system("cls");
cout << "Invalid sale amount. Please enter a positive amount : ";
cin >> salesAmount;
}
tempComm = salesAmount + (salesAmount * commRate);
cout << fixed << setprecision(2) << "Commission earned by tom on this sale is : " << tempComm << endl;
//cin.get();
amountT += salesAmount + tempComm;
commT += tempComm;
totalSales += amountT; // I think you mean to add salesAmount maybe?
}
break;
}
} //while (inputSalesPerson != 'z' || 'Z');
// Even if { this ^^^^} is false, ^^^ this is always
// 'Z' char will convert to bool, any non-zero value is true.
while (inputSalesPerson != 'z' && inputSalesPerson != 'Z');
return 0;
}