recursive function return Without return

[ynd]

In the following code, I wrote a function recursively which should return a value, and really when two numbers are equal it returns, in the function I did not use the return and she is still working, I'd love to get an answer to why it works?

  #include <iostream>
#include <string.h>
using namespace std;

int gcd(int num1, int num2);

void main()
{
    int ret_num = gcd(24, 60);
    cout << ret_num << endl;
}

int gcd(int num1, int num2)
{
    if (num1 == num2)
        return num1;
    else
    {
        if (num1 < num2)
            gcd(num1, num2 - num1);
        else
            gcd(num2, num1 - num2);
    }
}

[Little Bobby Tables]

first of all, why are you using string.h?
second of all, dont use void main
third of all i think its just undefined behavior. what compiler are you using?

[ynd]

Why not use string.h?
I ran into Visual Studio 2013 also and Linux with g ++ compiler
Visual studio it's not showing me any error or warning.

[Militie]

<string.h>
This is the C string functions. This file contains functions defined for the "C" programming language (Not C++), things like strlen() and strcpy().

<string>
This is the correct one to use as you will be able to do more with the C++ std::string class. Since you are programming in C++ you will want to use <string>.

Now if you intend to use <string.h> (Which I 99% suspect you don't) You would need to actually use <cstring>.

------------------------------------------------------------------------------------------------------------------

Now, why not to use void main(), the super simplified answer is that C++ kind of requires main() to return an int value. Just think of it this way. It is a standard that you are required to adhere to. In the same kind of standard that you cannot name your main() function superCOOLmainfunction(). It just has to be int main().

[Little Bobby Tables]

a) youre not using anything in it
b) thats a c library. the proper one would be <cstring>
c) if youre using c++, you might as well use <string> ie the std::string class. what version of g++ are you using?