Functions - Help!

[autoprogrammer]

Hi, I'm not so great with C programming, however in this assignment I'm supposed to use this function:

int
find_div(int n)
{
  int trial,
      divisor;

  if (even(n)) {
    divisor = 2; 

  }else{
    divisor = 0;
    trial = 3;
  }

  while (divisor == 0) {
    if (trial > sqrt (n))
      divisor = n;
    else if ((n % trial)==0)
      divisor = trial;
    else
      trial += 2;
  }
  return (divisor);
}

This is pretty much copied directly out of the book but it will not compile. I'm pulling my hair out trying to figure it out but I'm sure someone here could spot the problem in a second. Thanks!

[matsp]

It would help quite a bit if you indicated:
1. What the error message is.
2. Mark the line in the post that the error refers to.

--
Mats

[autoprogrammer]

Sorry, the one I can't seem to shake no matter what is that it is expecting a token before the initial { after "int find_div(int n)"

[matsp]

Sorry, the one I can't seem to shake no matter what is that it is expecting a token before the initial { after "int find_div(int n)"

Then you most likely have something wrong on the line BEFORE that, OR you have some invisible character in the file that we can't see here.

--
Mats

[C_ntua]

You haven't posted the whole code. Maybe you just miss a } in your main program? I mean, this cannot compile without a main...

[autoprogrammer]

I got rid of the token error but now it tells me the "called object is not a function" in the line where it says "divisor = 2;"

#include <stdio.h> /* printf, scanf definitions */
#include <math.h>

int
main (void){

  int even,
 

int
find_div(int n)
{
  int trial,
      divisor;

  if (even(n)) {
    divisor = 2; 

  }else{
    divisor = 0;
    trial = 3;
  }

  while (divisor == 0) {
    if (trial > sqrt (n))
      divisor = n;
    else if ((n &#37; trial)==0)
      divisor = trial;
    else
      trial += 2;
  }
  return (divisor);
}

}

I haven't really gotten much further than this yet...

[matsp]

int
main (void){

  int even,

is not a complete function, so perhaps you need to consider completing the main function - at least to such an extent that the compiler can proceed to compile the next function. In this case, you have an incomplete line of variable declaration, and a missing brace to complete the main - at the very least.

It is a good idea to compile often, but it's not particularly meaningfull to compile unfinished code - in this case it's a bit like the painters coming into your new house to paint your front room, but the bricklayer is still there finishin the second half of the wall.

Often, when working on a project, you may find that making place-holder functions that are "incomplete code, but framework complete" - that is, you have all the "walls" in place, but not all details of the code "the bits that go on the walls (radiators, plug sockets, phone jacks, etc)".

--
Mats

[Smattacus]

You should note that one does not include function declarations and definitions inside of main! What you're doing now is just that; your bracket finishing main is at the end of the entire program! Usually programmers write additional functions like this:

int main(void) {
//Do some stuff, add things, subtract others, etc:
int a1, a2;
a1 = function1(5, 3, ...);

}

int function1(int arg1, int arg2, ...) {
// Define the function here
}

int function2(int arg2, int arg2, ...) {
//Define another function
}

The "walls" in matsp's analogy are these function declarations. You can in fact just declare them with some arguments and return some generic value (NULL works great for this) and then call them in your main, and the compiler will happily trundle along, like so:

int function1(int arg1, int arg2){
return NULL;
}

But this is beside the point of what you are doing. Look at the framework I gave, and look at your program. What would you do to fix it to make it structured like mine?

[yahoosilver]

you should use a coding standard so everybody would understand it

[master5001]

Smattacus, I am aware of your religious beliefs which formally exclude the usage of proper tabbing, but feel free to just humor those of us who don't like to reformat your code to read it, copy and paste it into VC++ and hit ctrl+k,ctrl+f, or simply just use our years of reading crappy coding experience.

[Smattacus]

My bad I forgot since I was just writing out a semi - psuedo code example in the thread. Here's a tabbed version for those who care.

int main(void) {
	//Do some stuff, add things, subtract others, etc:
	int a1, a2;
	a1 = function1(5, 3, ...);

}

int function1(int arg1, int arg2, ...) {
	// Define the function here
}

int function2(int arg2, int arg2, ...) {
	//Define another function
}

Hooray!

[master5001]

Thanks I know sometimes I seem like I am being both petty and pedantic, but newcomers may benefit from your code too! So I think its only right to give them an opportunity to also be able to fully have a fighting chance in hell to understand your code and not get hung up on syntax.