#include <initializer_list>
#include <iostream>

using namespace std;

void foo(const initializer_list<int>& row_vector) { cout << size(row_vector) << "x1 - FIRST\n"; }
void foo(const initializer_list<initializer_list<int>>& matrix) { cout << size(matrix) << 'x' << size(*begin(matrix)) << " - SECOND\n"; }

int main() {
	foo({ 1, 2, 3 });
	foo({ { 1, 2, 3 }, { 4, 5, 6 }, { 7, 8, 9 } });
	foo({ { 1 }, { 2 }, { 3 } });
}