C++ - Comma Operator
Comma is an operator in C++. When comma is with in paranthesis, the right most argument is taken as a result otherwise left most.
int a, b, m , n;
a = 10;
b = 20;
m = (a,b); // m will hold the value of b which is 20
n = a,b; // m will hold the value of b which is 10
std::cout << m, n; // The code prints the output 20,10