Question

Is it considered proper to have code like this:

#include <FILEHERE>
using namespace std;

char input;

int main() {
    cin >> input;
    cout << input;

    return 0;
}

I know that this code will work, but is is considered proper and is there a better wat to do it?

The reason I am using code similar to this, (but far more complex), is because I have a thread and the main function both using this string at some point, and the only way I could think to declare it for both the thread and main function was to declare it outside the thread and main function. What is a better way to do this?

EDIT: I am not asking about using namespace std; as I use it in almost every program I write.

Answer 1

You can pass a pointer to a variable local to main thread:

int main() { 
  int input;
  set_thread_input(&input);
  /* ... */
  return 0;
}

void thread_func(void *arg){
   int *input = (int*)arg;
   /* ... */
}