[SOLVED] printing a through g using a while loop in c language

UnixCube · 04-09-2012, 03:10 PM

@suicidaleggroll, thank you.

I just initialized the character variable ch to the string value 'A' and I think that is what fixed my error. Before that initialization you were right, the value that I had initially stored was all nonsense. Thank you again.

suicidaleggroll · 04-09-2012, 03:14 PM

What you have there will work. It's a little overly complex for my taste (for example, why is the variable a running from 65 to 72 instead of 0 to 7? why are you using ++a instead of a++? just little nitpicky things like that), but it will work consistently.

UnixCube · 04-09-2012, 03:16 PM

Thanks suicidaleggroll, I fixed the problem by initializing the char ch variable to 'A'. That helped out a lot.

suicidaleggroll · 04-09-2012, 03:22 PM

I know you already solved this, but sometimes it helps to see other solutions to the same problem. Here is what I would probably do for this:

Code:

#include <stdio.h>

int main (void)
{
        char a;
        for (a='A';a<='G';a++) printf("%5c",a);
        printf("\n");
        return 0;
}

End result is the same, but it's a little easier to follow, and would probably execute a bit faster since you only have one variable being incremented every iteration of the loop instead of two. Just another way of approaching the problem.

273 · 04-09-2012, 03:25 PM

Quote:

Originally Posted by suicidaleggroll

You NEVER want to use a variable before you initialize it to something.

Quoted in agreement.

UnixCube · 04-09-2012, 03:27 PM

@suicidaleggroll
I think that it could work that way using the for loop as well. You are right. I only chose the while loop for the practice. Also, I tried changing the while condition using the range from 0 to 7, and that did not work. I have to keep the condition from ++ch < = 72, or it will give me an infinite loop.

Nylex · 04-09-2012, 03:41 PM

You know you can compare against character literals too, right? The value 72 is not particularly useful (unless you can remember the ASCII values). I find it more readable to use the character you're interested in comparing with (as suicidaleggroll did above). With a while loop, this is (C++; obviously you can use printf() rather than cout), e.g.

Code:

char ch = 'A';
  
while(ch <= 'G')
{
  cout << ch << endl;
  ch++;
}

suicidaleggroll · 04-09-2012, 03:48 PM

Quote:

Originally Posted by UnixCube

Also, I tried changing the while condition using the range from 0 to 7, and that did not work. I have to keep the condition from ++ch < = 72, or it will give me an infinite loop.

You must not have done it correctly.

Code:

int a = 65;
while ( ++a <= 72  )
{
   do stuff with ch
}

is exactly the same as

Code:

int a = 0;
while ( ++a <= 7  )
{
   do stuff with ch
}

UnixCube · 04-09-2012, 03:52 PM

suicidaleggroll

I am going to try some more with the code, that you are talking about. Using different conditions for the while loop. I think I did it wrong when I put the values in myself, I will try again.