You are supposed to pass the variable spade, not spade[0,13] (is that even valid syntax?).
I am getting a little confused by Java at the moment, but in C++ I would write it as:
Code:void displayCards(string spade[])
{
for (int i=0; i<13; i++)
cout << "S: " << spade[i];
}
// To call it.
displayCards(spade);