Thread: String/Int Length Issue

Hello, I have just recently (yesterday) began learning cpp. I have been going over the tutorials offered on this site and I have stumbled across a small problem. I am attempting to create a tester program to see if I am grasping what I have learned so far. My problem occurs when I attempt to discover the length of an integer.

I am aware of the strlen function that will return the length of a string. However I desire to know the length of variable that is an integer.

So far I have tried making a string that variable but the compiler refuses on the grounds that it cannot accept a 'char string' is equal to an 'int variable'. Like so

Code:

...
char vse[15];
int vx;
...
vse=vx;
...

I understand that it cannot be done this way.

Then I reread typcasting, in hopes that I could find a way to play with the int/char types and be allowed to convert my int variable into a string and use strlen. Unfortuneatly I cannot figure out a feasible way to use typcasting to solve my problem.

In short, I am looking for a way to know how many digits a number has.
ie:
1 -->1
11 -->2
111 --> 3
1111 --> 4
...

Is there a way to find this?

Cheers,
Smiley

Ah of course! Thank you Anon, I can't beleive I did not think to count the number of times I could divide the number by 10. I created this litte function that has acheived my goal flawlessly, thank's again Anon.

Code:

int digam(int oi) {
  if (oi!=0) {
    int in = 0;
    while (oi>0) {
      in++;
      oi /= 10;
    }
    return in;
  }
  else {
    return 1;
    }
}

I though this the most logical approach to doing this. Although I suspect it might not be as optimised as it could be, it works nonetheless.

iMalc, you also bring an answer to my question, and a very interesting one. I wonder, though, is 'stringstream' a variable type(like 'int' and 'char')? Also, when you call it s.str() is that what I should type if I want to return the value/word?

I'm sorry for having several questions but this seems like a very interesting and useful method to learn, and I would much like to understand.

Again I thank the both of you, you're help was greatly appreciated.

Cheers,
Smiley

Oh, thanks a lot iMalc, knowing this will help a great deal. I have read through the link you gave me a couple of times and it seems to be sinking in. I'll go over it a couple more times and play around with it to be fully comfortable with it. Thanks again.

Cornedbee, thank you for a more concise version of the function. If I understand correctly, the do...while loop is more efficient than a while loop? Is this because the do..while executes the loop once and then checks to go on, instead of checking every-time before executing, as the while loop does?

I apologies if this all sounds overly basic, but I like to be sure of my facts when I learn something. If the foundation is weak then the building cannot hope to be solid.

Thanks again,
Smiley

Ah, I admit it does allow for a better read. Thanks again for the help, I honestly appreciate your time.

Cheers,
Smiley