#include <array>
#include <iostream>
 
template <typename ...ArgsT>
void foobar (ArgsT ...a) {
    std::array<int, sizeof... (ArgsT)> args {a...};
    std::cout << "{";
    for (auto i : args) std::cout << i;
    std::cout << "}\n";
}
 
int main () {
    foobar ();
    foobar (1, 2, 3);
}