public Deck() {
           // Create an unshuffled deck of cards.
       deck = new Card[52];
       int cardCt = 0; // How many cards have been created so far.
       for ( int nSuit = 0; nSuit <= 3; nSuit++ ) {
          for ( int nValue = 1; nValue <= 13; nValue++ ) {
             deck[cardCt] = new Card(nValue,nSuit);
             cardCt++;
          }
       }
       nCardsUsed = 0;
    }