Im learning C online, and one of the examples from the internet is this:

#include <stdio.h>

int CalcVolume (int length, int width, int height);

void PrintIt (int vol);

void main()
int volume1, volume2;
int x = 8, y = 15, z = 20;
volume1 = CalcVolume (10, 20, 30);
PrintIt (volume1);
volume2 = CalcVolume (x, y, z);		
PrintIt (volume2);	

/* end of main */	

int CalcVolume (int length, int width, int height)	


int vol;	
vol = length * width * height;
return vol;	
/* end of CalcVolume */

void PrintIt (int vol)
printf("The volume is: %d\n", vol);

but when im trying to compile it sais

ch5m.c: In function ‘main’:
ch5m.c:9: warning: return type of ‘main’ is not ‘int’

is there an error in the exesize?


Some C compiler will give you a warning when your main function does not return an integer.

In this case, do the following changes to the main function:

int main()
return 0;

you can also use the above statement as
void main()
since in using the void function you need have to use return anything.