Re: how to specify power of number

Ben Bacarisse <ben.usenet@xxxxxxxxx> wrote in
news:87od877aoh.fsf@xxxxxxxxx:

Yanb <Yanb@xxxxxxxxxxxxxxxx> writes:

Hi, I'm new to c, so please excuse, if this is silly ;-)

Well, not silly, but I am surprised that you start a new language
without consulting some sort of reference.

Hi, and thank you for reply. I have read some very basics, but usually I need a language for a specific
thing and as soon as I know enough to complete the task, I leave learning till later :-/

Do you have some tip for a newbie where to start? Of course I can google out load of pages about c,
but no search engine can compete with reference from a human ;-)


I made a C function, which takes IP adress from string and converts
to unsigned long int. Everything works, but I found that the
"counting" part part works only with this:

numericip=atoi(textip[0])*256*256*256+atoi(textip[1])*256*256+atoi(tex
tip[2])*256+atoi(textip[3]);

When I wrote *(256^3), I got fake results. I'd like to use something
more sophisticated, instead of 256*256

^ is exclusive or in C. C does not have an exponentiation operator.
Most C programmers would use a shift (<<) by 24, 16 or 8 bits to
compute the value you want.


Oh yes, that's it, thanks, shifting I know shifts from php ;-) This way will need less cpu cycles than
multiplication.

Ok, so there no way to write mathematic "power of" in c?
.

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