Newbie programmer with his first frustration

Hello my first post brings with it my first c++ problem. Having no previous coding experience, I went out and bought C++ Without Fear as recommended by the site and ran into difficulties with the first if/else lesson. It's also the first lesson using the % as a division mechanic. Im using Visual Studio C++ express edition for this.

Code:

---

#include <stdafx.h>
#include <iostream>
using namespace std;

int main()
{
        int  n, remainder;

        cout << "Enter a number and press ENTER: ";
        cin >> n;
        remainder = n % 2;
        if (remainder == 0)
                cout << "The number is even.";
        else
                cout << "The number is odd.";

        return 0;
}

---

Ive looked at the example 5-6 times now and am quite sure that I've copied it verbatim, but this is the first time that I've entered something without it working at all. Any ideas as to what Im doing wrong?

you can start by telling us what's not working.

I hit Ctrl + F5 to try to start the program but I get an error message that says there were build errors, and it wont run the program.

You are going to have to be more specific. What build errors are you getting?

The code you posted above is correct, so it is most likely due to a problem with the way your project is set up.

Hello, I tested out your code and I found the problem. You need a while statement. I am using while (1), which will keep executing your code. Nice beginner program, never actually thought about making one of those. Also you have good algorithm design for a newbie. Also the only library you need is iostream. It works fine. Here is the refined code...

Code:

---

#include <iostream>
using namespace std;

int main()
{
        int  n, remainder;
    while (1)
    {
        cout << "Enter a number and press ENTER: ";
        cin >> n;
        remainder = n % 2;
        if (remainder == 0)
                cout << "The number is even.";
        else
                cout << "The number is odd.";
    }
        return 0;
}

---

Nice program, and keep programming ^^

There is no need for a while statement in that program.

galactic_ronin: Please post the errors you are getting, be as specific as possible (ie post the full error message). Also mark the lines in the code so we know which error lines up with which line of code. Best of luck.

I made it work..What are you talking about? And now it's better.

Quote:

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Originally Posted by PЯO

I made it work..What are you talking about? And now it's better.

---

How does it stop, exactly?

Edit: Although I will give you credit for probably stumbling over the issue, since I'd be willing to bet at least a dime that the problem is the stdafx.h line. Shouldn't that be in quotes?

It should be, but Pro didn't stumble upon the issue. The problem is in the project settings (my guess is it's a GUI app and can't find WinMain), and Pro set up a new project where it works. Won't help the OP.

If its finding odd and even this is a much easier way:

Code:

---

if (( number % 2 ) == 0 )
{
  std::cout << "\nNumber is even!\n";
}

else
  std::cout << "\nNumber is odd!\n";

---

Irrevelant posts have been deleted. If you want to discuss the merits of one IDE over another, or the command line versus a GUI, go do it elsewhere.

Quote:

---

Originally Posted by swgh

If its finding odd and even this is a much easier way:

Code:

---

if (( number % 2 ) == 0 )
{
  std::cout << "\nNumber is even!\n";
}

else
  std::cout << "\nNumber is odd!\n";

---

---

You could also optimize it by checking if the lowest bit is set ;)

Code:

---

if (number & 1)
{
  std::cout << "\nNumber is odd!\n";
}

else
  std::cout << "\nNumber is even!\n";

---

fair nuff laserlight.

I don't want to get off topic again so might I suggest some IDE tutorials on the site?

Quote:

---

Originally Posted by mike_g

You could also optimize it by checking if the lowest bit is set ;)

Code:

---

if (number & 1)
{
  std::cout << "\nNumber is odd!\n";
}

else
  std::cout << "\nNumber is even!\n";

---

---

A trap into which I've fallen, too. But you shouldn't do that if there's any chance that the number is negative. Some negative number representations have the bits flipped around.

Trust the compiler to optimize %2 to &1 if it's safe. I'm pretty sure most of them do it if you compile with optimizations.