Explaination of this code, anyone?

Question

What is the output of this code?
#define macro(r, a, b) b##a##r
#define CHAOS macro(r, a, b)
void CHAOS(int n) { printf("%d", n); }

int main() {
bar(4);
bar(2);
return 0;
}

Answer 1

Thank you so much, Rewa Mathur!!

Answer 2

What is bar(4) bar(2) meant to be doing here?

Answer 3

preyash gothane okay got it!! Thank you!!

Answer 4

I guess this will help you
.
https://gcc.gnu.org/onlinedocs/cpp/Macros.html

Answer 5

In that link I shared read this
"Object-likemacros resemble data objects when used, function-like macros resemble function calls"
So those bar are like objects I guess