#include <iostream>

// Source - https://stackoverflow.com/a/10616756
// Posted by Jon, modified by community. See post 'Timeline' for change history
// Retrieved 2025-12-12, License - CC BY-SA 3.0

#define OUT(x) if((x > 0 ? cout << "Hello " : cout), x > 1) cout << x+1


using namespace std;

int main() {
OUT(1) << "message";     // OK

if(0) {
   OUT(1) << "message";     // OK, nothing printed
}

if(0)
   OUT(1) << "message";     // Now nothing is printed
	
	return 0;
}