main_array.cpp: In function ‘int main(int, const char**)’:
main_array.cpp:12:12: error: no match for ‘operator<<’ (operand types are ‘std::ostream {aka std::basic_ostream<char>}’ and ‘Array’)
  std::cout << mya;

ostream& operator<<(ostream& output, Array const& data)
{
    for (int i = 0 ; i < data.size() ;i++)
    {
        output << data.at(i);
    }

    return output;

int main(int argc, char const *argv[])
{

    Array mya(2); //creates 0`s array

    std::cout << mya;

    return 0;
}