Program runs but does not output desired results

Apr 10, 2012 at 5:18pm
cokane (31)
I need to get this program to ignore even numbers and only add positive ODD numbers. The loop is designed to end when the user inputs "-1" and this feature works. The problem I am having is my code doesn't print the show the results of the addition, or when I can get the program to print the results out the number I am getting back is WRONG. 

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#include <iostream>
using namespace std;

int main()
{
  int in;
  int total = 0;

  while (true) {
    cout << "Enter a positive odd number or -1 to get quit ";
    cin >> in;
    if (in <= 0) {
      break;
    } else if (in % 2 == 0) {
      total += in;
      cout << total;
      cout << " The total number of odd intergers equals = " << total + in << endl;
    }
  }
}
Edit & run on cpp.sh
Last edited on Apr 10, 2012 at 5:24pm
Apr 10, 2012 at 6:18pm
Disch (13742)
look at line 14 more closely and ask yourself what it is doing.

Remember that % gives you remainder after division. So if in % 2 gives you zero, what does that tell you about 'in'?

Also, you summed 'in' on line 15, so why are you adding it again on line 17?
Apr 10, 2012 at 9:58pm
cokane (31)
I have been working on this but still can't get it add the numbers right. 
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  int in;
  int total = 0;

  while (true) {
    cout << "Enter a positive odd number or -1 to get quit ";
    cout << "\n";
    cin >> in;
    if (in <= 0) {
      break;
    } else if (!in / 2 == 0) {
      total = total + in;
      total++;
      cout << "The total number of odd intergers equals = " << total  << endl;
    }
  }
}
Apr 10, 2012 at 11:06pm
Disch (13742)
You were closer with your first attempt.

else if (!in / 2 == 0) { <-- I don't know what you were trying to do here, but that's all wrong.


else if (in % 2 == 0) { <-- this is very close.

Remember how the % operator works. It gives you the remainder after division.

So...

0 % 2 == 0  (0 / 2 is 0 remainder 0)
1 % 2 == 1  (1 / 2 is 0r1)
2 % 2 == 0  (2 / 2 is 1r0)
3 % 2 == 1  (3 / 2 is 1r1)


So with that in mind.... if you are doing if (in % 2 == 0), what are you actually checking for?



Also, why are you incrementing the total on line 12?
Apr 10, 2012 at 11:36pm
cokane (31)
So with that in mind.... if you are doing if (in % 2 == 0), what are you actually checking for?

I am trying and failing to make the program ignore even numbers



Also, why are you incrementing the total on line 12?

I thought I needed to increment it so it would do a running total of all odd numbers.
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