Thread: Problems with array of strings

The most common way is to read a string with fgets, then convert to float using strtod, and check the end pointer argument to see where the function stopped parsing. If it stopped parsing right away (the start is the same as the end), then it means it's an invalid input.
You can see documentation for strtod.

Thanks for an idea, but therefore I've faced another problem. I decided to use isdigit to check if the inputed number is not a char and if it isn't-then convert it with atof or atoi.

But then i started to use these funcions, the for loops began working incorrectly: they are being repeated more times than the num value is, for example if num=3, each loop is repeated10 times and so on.

Do you have an idea how could I correct this to work properly?

Code:

   char t;

               for(i=0;i<num;i++)
                    {
		char* p;
		printf("Enter string nr.&#37;d\n",i+1);
		fgets(string[i], sizeof string[i], stdin);
		p = strchr(string[i],'\n');
		if(p) *p = '\0';
	     }

                for(i=0;i<num;i++)
	{ 
                       printf("Enter float nr.%d \n",i+1);
	               fgets(&t, sizeof &t, stdin);
	               if (isdigit(t)) floatt[i]=atof(&t);
	               else {printf("Error");return 0;}
                 }

 
               for(i=0;i<num;i++)
                 {	
                     printf("Enter integer nr.%d \n",i+1);
	             fgets(&t, sizeof &t, stdin);
	             if (isdigit(t)) integer[i]=atoi(&t);
	             else {printf("Error");return 0;}
	}

You are aware that there are valid floating point numbers that do not start with a digit:

Code:

+1.2
-1.2
.01

Above are three examples of such numbers.

By using strtod(), you can make a better check if the number is valid (and completely accepted - you then can decide if "123.4A" is a valid number or not).

--
Mats

I don't know how string is defined, but this is absolutely wrong:

Code:

fgets(&t, sizeof &t, stdin);
if (isdigit(t)) floatt[i]=atof(&t);

When working with C-strings, you need arrays, not a single char. Never. All C-strings contains one byte for each character + one character for NULL. So when reading that char, fgets write the char + NULL, thus buffer overrun. The same for atoi - it also expects a NULL char, and does a buffer overrun looking for it.
http://cpwiki.sf.net/Buffer_overrun

But you seriously need some indenting lessons too. Here are some reasources:
http://cpwiki.sf.net/Indentation
http://cpwiki.sf.net/User:Elysia/Indentation

How? What compiler are you using? If you are using Dev-C++, did you use getche()? (Just out of curiosity.)

By the way, that smiley that you keep using ( ) is not used when asking for help. Actually, it indicates sarcasm, which usually means you're annoyed or something -- which I don't think is what you want to convey.