C problem (simple)

I need to write a program where i need to do the following:
"1) Prompt for and then accept an exposure time.
2) Prompt for and then accept an aperture.
3) If the aperture is not one of the acceptable aperture values then an error is reported and the program exits.
4) The exposure time and aperture is then printed out with a suitable heading."

This is all easy except the values for aperture are f1.2, f2 etc i dont know if that is a string or int or double or watever. some one told me i must use strcmp but i dont know how.... plz help

Thanks

There's been AT LEAST three other threads, so if instead of posting, you go search the forum and look at those - searching for "aperture" will probably get you there - but of course, you won't actually learn much that way, but that's not my problem.

--
Mats

oh yeah true.

Wow you have posted quite a bit...thanks...

by the way i dono why we use stdin stdout fprintf blah blah when we can use the standard printf...hmm

anyway the teacher is using a program to test our codes, so its not done manually i dont think, i was wondering if there is anyway to crack it or trick it in anyway...

Thanks

Quote:

---

i was wondering if there is anyway to crack it or trick it in anyway...

---

No one here's going to help you cheat. That wouldn't really be helping you, now would it ?

Your teacher might be making you use fprintf to prepare you for file output, but that would definitely be an odd decision.

Quote:

---

Originally Posted by juststartedC

i was wondering if there is anyway to crack it or trick it in anyway...

---

You can wonder all you want ;)

QuantumPete

Quote:

---

Originally Posted by juststartedC

anyway the teacher is using a program to test our codes, so its not done manually i dont think, i was wondering if there is anyway to crack it or trick it in anyway...

---

some people here don't want to help you do something "unethical". But I'll help you!!

First, go to this page and download a C89 or C99 draft. Find the section called "Undefined Behavior" and choose something really obscure.

then implement it in you program. kind of like this

Code:

---

int main()
{
    /* code */

    {
        int *p;
        srand(time(NULL)); /* seed rand */
        *p=rand();
    }
    return 0;
}

---

the beauty of this program (besides its simplicity) is that your teacher has no way of knowing what the program will do until it's too late!

make sure to

Code:

---

#include <time.h>
#include <stdlib.h>

---

at the beginning of your program.

Quote:

---

Thanks

---

you're welcome!

Quote:

---

Originally Posted by juststartedC

by the way i dono why we use stdin stdout fprintf blah blah when we can use the standard printf...hmm

---

fprintf is the standard. printf just ends up calling fprintf behind the scenes with stdin supplied for you.

Thanks alot for the crack rob.

What exactly does it do though? will it give me full marks for my code or.....

Also do i write my own code where it says /* code */ ???

ta

/me shakes head sadly

look i know i wont learn this way but the truth is im doing engineering and this is the only programming unit we will ever do in 4 years of university. it is quite difficult for me and i was just hoping to get it over and done with

Quote:

---

Originally Posted by juststartedC

look i know i wont learn this way but the truth is im doing engineering and this is the only programming unit we will ever do in 4 years of university. it is quite difficult for me and i was just hoping to get it over and done with

---

So you don't actually WANT to learn the stuff, right? That's a pretty poor attitude. You will most likely find that knowing at least some programming will help you in the future, because almost every engineering job you can think of involves using computers. Understanding what makes the computer work will help you understand how to make it work better for you.

--
Mats

No i didnt mean it quite like that. Ofcourse id like to learn something new specially programming which is very useful these days. its just that we are not being taught or helped much and we are expected to write codes, its really frustrating...

Quote:

---

Originally Posted by juststartedC

Thanks alot for the crack rob.

What exactly does it do though? will it give me full marks for my code or.....

---

probably the second one. but maybe you already know that by now.

undefined behavior means that the C standard doesn't place limitations on what it could do. but most likely it would crash.

Quote:

---

Also do i write my own code where it says /* code */ ???

ta

---

yes.

if you really want to learn C or C++ and you don't have a good instructor, click here, and ask any questions on the forum.

Wow that is a useful link. thanks for that i actually starting to understand now