What is this format? A list? An array?

Question

#include <iostream>
using namespace std;

int main() {
int x = (1,2,3,4,5);
cout << x;
}

// output is the 5 (or whatever is the last integer within the parenthesis)

What concept is being tested here?

Answer 1

Comma operator 👇

http://en.wikipedia.org/wiki/Comma_operator

http://www.c4learn.com/c-programming/c-comma-operator/