Functions with c

techintraining · 24-10-2016 11:07PM #1

Hi,

Wondering if anyone could explain this code for me, i have a test tomorrow and im looking at a fail right now, not for the lack of effort, i mean its open book i just really cant understand this i just got to grips with for loops and the test is on functions -_-

Question 2

What is the value of the variable c in the main function after the following code is executed?

/* function prototypes
(prototypes let the compiler know what functions your program is going to use)
*/
int myfunction(int var1, int var2);
void my_other_function(int var1);
int main()
{
int c, b;
b = 7;
c = myfunction(4, b);
my_other_function(2);
return 0;
}
int myfunction(int var1, int var2)
{
int a;
a = var1 + var2;
return(a);
}
void my_other_function(int var2)
{
int c;
c = var2;
}

Thanks,
Mark

bonzodog2 · 25-10-2016 11:00AM

I'm not going through it line by line, but c in main will have the value 11 after the 1st function is called; the second function has no effect as it only changes its own local variable c, which is then discarded.

PrzemoF · 25-10-2016 02:09PM

/* function prototypes
   (prototypes let the compiler know what functions your program is going to use)
 */

int myfunction(int var1, int var2);
void my_other_function(int var1);

int main()
{
	int c, b;
	b = 7;
	c = myfunction(4, b);
	my_other_function(2);
	return 0;
}

int myfunction(int var1, int var2)
{
	int a;
	a = var1 + var2;
	return(a);
}

void my_other_function(int var2)
{
	int c;
	c = var2;
}

Add

printf("%i", c);

before return (0);
Go to http://www.learn-c.org/ and test the code at the bottom of the page.
Search for c for beginners and read anything about c - that will explain you what's happening here (main, void, int, return is all you need to understand)

11

jimgoose · 25-10-2016 02:14PM

Have a read of this:

https://en.wikipedia.org/wiki/Local_variable

The key to the thing is these lines:

c = myfunction(4, b); 
..
..
return(a);

And tell the lecturer that wrote that that (s)he's looking for a kick up the hole with that layout and indentation.

PrzemoF · 25-10-2016 02:17PM

Naming convention is below any standard as well

Functions with c

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