can i write function definitions in header files?

Question

i just cut all my functions in main.c and pasted them in a header file to make it look cleaner and included that in main.c, now its not compiling what should i do instead

Answer 1

You can do that, but you will need another source file too. For example:

func.h
void printHello();

func.cpp
void printHello() {
cout << "Hello!\n";
}

And then in main.cpp
#include "func.h";
...
printHello();
...

Whenever I have functions that I don't want filling up my main file, I'll put them in separate files like that and I usually call them Utility.h and Utility.cpp. I'll also wrap the file in a namespace so I know where they came from.

func.h
namespace Utility {
void printHello();
}

func.cpp
void Utility::printHello() { };

Answer 2

Yes the have to

Answer 3

does the .h and .cpp files need to have the same name