How do I continue to the second main2() from main()? [closed] - c++

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I have a problem. Here is the simplified version:
#include <iostream>
using namespace std;
int main() {
cout << "Hello!";
return 0;
}
string name = "My name is ______";
int main2() {
cout << name;
return 0;
}
I have tried to remove the first return 0; in the main(), but it did nothing. I want to somehow start main2() from main(). Is it possible?
I tried running the code(I use repl.it) and it didn't return any error messages. I also tried running it from the Terminal and it just prints Hello!.

Answer 1

Yes. Try something like this:
#include <iostream>
using namespace std;
// Forward declare |main2|.
int main2();
int main() {
cout << "Hello!";
main2();
return 0;
}
string name = "My name is ______";
int main2() {
cout << name;
return 0;
}
To elaborate on the differences between C++ and Python here: In C++ main is the entry point for your program. So in C++, you can think of the start of the main function as the equivalent of Python's "top of the file". Your program will begin running at the top of main, and stop running at the end of it. Anything that is not invoked starting from the main function (or transitively invoked) will not be executed.

Answer 2

What you wrote is roughly equivalent to the following Python:
def main():
print('Hello')
return 0
name = 'My name is ____'
def main2():
print(name)
return 0
if __name__ == '__main__'
sys.exit(main())
I believe now it's clear why main2 never gets executed: it's never called.
Note that the main function in C++ is the one function which gets called automatically at program start, and exiting main terminates the program. Whatever you want to happen while your program is running must be called from within main.
Also note that a name (such as a function) must be declared before it can be used. So you'll have to either move the definition of main2 before that of main, or at least declare main2 there. Which you could do like this:
#include <iostream>
using namespace std;
int main2();
int main() {
cout << "Hello!";
return main2();
}
string name = "My name is ______";
int main2() {
cout << name;
return 0;
}

Answer 3

You have to call main2() inside main():
#include <iostream>
using namespace std;
string name = "My name is ______";
int main2() {
cout << name;
return 0;
}
int main() {
cout << "Hello!";
main2();
return 0;
}