C++: Trouble with ending a loop based on a condition? - c++

Question

This code is used to run a loop three times, that takes the numbers of eggs gathered and outputs the number in dozens and extra until the user enters a negative number. Then, it prints out the average amount of eggs gathered (entered), and outputs the total number of dozens and extra.
The inputs we were assigned to use are:
43,
31,
-1,
24,
8,
14,
-999,
-5.
Everything is fine up until we input -5. Our teacher doesn't want the average or total number of dozens and extras to print (you'll see what I mean in the output).
The source code is as follows:
#include <iostream>
#include <iomanip>
using namespace std;
int main ()
{
int eggNum;
int eggDozens;
int eggExtra;
int eggTotal;
int loopCount;
int forCount;
float eggAvg;
int totalDozens;
int totalExtra;
for(forCount = 1; forCount <= 3; forCount=forCount + 1)
{
cout << left << "TEST #" << forCount << ":" << endl;
cout << "Welcome to Aunt Ellen\'s eggs to dozens converter!";
cout << endl << endl;
cout << "\tEnter the number of eggs gathered: ";
cin >> eggNum;
eggTotal = 0;
loopCount = 0;
while(eggNum >= 0)
{
eggDozens = eggNum / 12;
eggExtra = eggNum % 12;
if(eggDozens != 0)
{
if(eggExtra != 0)
{
cout << "\tYou have " << eggDozens << " dozen ";
cout << eggExtra << " eggs.";
cout << endl << endl;
}
else
{
cout << "\tYou have " << eggDozens << " dozen eggs.";
cout << endl << endl;
}
}
else
{
cout << "\tYou have " << eggExtra << " eggs.";
cout << endl << endl;
}
loopCount = loopCount + 1;
eggTotal = eggTotal + eggNum;
cout << "\tEnter the number of eggs gathered: ";
cin >> eggNum;
}
cout << endl << "TOTALS:" << endl;
eggAvg = eggTotal / float(loopCount);
cout << "\tOn average " << eggAvg << " eggs have been";
cout << " gathered.";
totalDozens = eggTotal / 12;
totalExtra = eggTotal % 12;
cout << endl << "\tA total of " << totalDozens << " dozen ";
cout << totalExtra << " and eggs have been gathered!" << endl;
cout << endl << endl;
}
return 0;
}
And the output:
TEST #1:
Welcome to Aunt Ellen's eggs to dozens converter!
Enter the number of eggs gathered: 43
You have 3 dozen 7 eggs.
Enter the number of eggs gathered: 31
You have 2 dozen 7 eggs.
Enter the number of eggs gathered: -1
TOTALS:
On average 37 eggs have been gathered.
A total of 6 dozen 2 and eggs have been gathered!
TEST #2:
Welcome to Aunt Ellen's eggs to dozens converter!
Enter the number of eggs gathered: 24
You have 2 dozen eggs.
Enter the number of eggs gathered: 8
You have 8 eggs.
Enter the number of eggs gathered: 14
You have 1 dozen 2 eggs.
Enter the number of eggs gathered: -999
TOTALS:
On average 15.3333 eggs have been gathered.
A total of 3 dozen 10 and eggs have been gathered!
TEST #3:
Welcome to Aunt Ellen's eggs to dozens converter!
Enter the number of eggs gathered: -5
TOTALS:
On average -1.#IND eggs have been gathered.
A total of 0 dozen 0 and eggs have been gathered!
I don't want the very last "TOTALS" and the lines following. I want the program to terminate after entering -5.

Answer 1

The simplest thing is to do this before entering the while loop:
cin >> eggNum;
if (eggNum < 0)
break ;
That will quit the for loop, and return 0;
You may, if you want to, add some comments to the caller about entering negative numbers before calling break.

Answer 2

You mentioned that you only want to omit the last block of TOTALS.
You can simply add a special case to leave the outer loop early in this case.
Right before this block, but after the closing brace of the while loop.
cout << endl << "TOTALS:" << endl;
eggAvg = eggTotal / float(loopCount);
Insert this:
if (forCount == 3) break;
If you just want to avoid printing whenever the average is less than 0, then instead you should insert in the same location.
if (eggAvg < 0) continue;
This will skip the rest of that iteration of the for loop.

Answer 3

I think a simple answer to your problem would be to just put an if statement around the printing total code. Like this:
if(eggNum > -5){ //won't print for negative 5
cout << endl << "TOTALS:" << endl;
eggAvg = eggTotal / float(loopCount);
cout << "\tOn average " << eggAvg << " eggs have been";
cout << " gathered.";
totalDozens = eggTotal / 12;
totalExtra = eggTotal % 12;
cout << endl << "\tA total of " << totalDozens << " dozen ";
cout << totalExtra << " and eggs have been gathered!" << endl;
cout << endl << endl;
}
I hope this helps!