Bridge›› Atari User Vol.1 No.10››This program allows you to bid and play contract-bridge against the computer.›The standard of play is quite sophisticated so it uses storage-saving techniques›to permit the program to run in 16k.››Select the card you wish to play with the joystick. Bidding is done by typing›the particular bid you wish to make when it is your turn.››The game is in two parts - bidding and card-play. The computer randomly deals›four hands. You play South and the computer bids and plays the other hands.››Bidding›The game follows the Nottingham club bidding convention which is described›later. Bids are displayed at the top of the screen. Enter them by typing the›bid, followed by Return. When it is your turn you are prompted with 'BID ?'. The›bid format is a number, followed by the letter to indicate the suit.››For example, 1H for one heart, 3NT for three no-trumps, P for pass, and D for›double. The computer will not accept bids in the wrong format and will prompt›you again with 'BID ?'.››When bidding is finished, the computer asks you to type the identity of›"declarer", which is 1 for North, 2 for East, 3 for South or 4 for West.››You are then asked to type the contract say, 2NT or 3H and so on. This allows›you to play a hand that would otherwise be played by the computer, or permits›you to set a more challenging contract. You will find this useful.››Card-play›Plug the joystick into port 1. The contract is displayed at the top-left of the›screen.››The first card is played by the hand to the left of the declarer. "Dummy's" hand›is then displayed. When you are required to play a card, you will be prompted›with a '?' and the cursor will be displayed.››Using the joystick, place the cursor over the card you wish to play and press›the Fire button. The card will be played, and deleted from your hand. At the end›of the trick the screen displays the winner and the trick total for each hand.›To begin the next trick, press the Fire button.››Pressing the Fire button after trick 13 instigates a redeal and the bidding for›the next game begins.››Pressing the Esc key at any point in the card play also instigates a redeal as›soon as the next card is played.››* The display follows the normal format to be found in books, except that 'T'›represents Ten.››* Each hand is seperate, and should be bid to the highest contract feasible for›that hand.››* There is no 'vulnerability'.››* Each deal is random and yields interesting distributions.››Playing hints›The computer plays either to achieve the contract, if it is declarer, or to›defeat the contract if it is defence. It is not so concerned to get the maximum›number of tricks.››It is capable of developing various long-term strategies - it can duck tricks,›cross-trump, finesse, develop long suits and so on.››If you (South) are in defence, for example, the computer as your partner (North)›will join with you in a sensible strategy, just as a human partner may do.››But the computer will not recognise the convention "lead the fourth highest of›longest suit" in "no-trump" contracts. Also, if you hold KQ or QJ etc. and you›are in defence, lead the higher of the pair, or the computer will assume that›the opposition holds the higher card.››Bidding convention›Points are counted as ACE (4), KING (3), QUEEN (2) and JACK (1). This is a›simple convention to use without many of the more complex - and to my mind›obtuse - ingredients which impoverish the less than brilliant player's game. I›have set limits for the computer which make it competitive and seemingly able to›take risks.››Opening bids. The following are permissible:››1C (one club) 16-20 points. Partner is required to respond.›1D, 1H, 1S 12-15 points, with a five-card suit in the bid suit.›1NT 12-15 points, but with no five-card suit.›2C 12-15 points, with clubs as the five-card suit.›2D, 2H, 2S 20+ points, with a five-card suit in the bid suit.›2NT 20+ points without a five-card suit. Partner should respond.›3C, 3D, 3H, 3S Pre-empt. Between 8-11 points, with at least seven cards in the› bid suit.››Note that any other opening bid will not be understood by the computer. I would›not like to predict its response.››Responses. The following describes the normal responding bids to the above.››--------------------------------------------------------------------------------›After 1C›--------------------------------------------------------------------------------›* Less than 7 points - Respond 1D.›* Between 7-11 points - 1NT, or 1 'something' in a good suit.›* Between 12-15 points - Jump response to 2 'something'. If you have a five-card› suit, the 'something' should be that suit, otherwise NT.›* More than 15 points - Jump to 3 'something'.›* After 1D, 1H, 1S, 1NT, 2C - Responses are natural here, that is, more or less› what you would expect. The responding bid lets partner know your points and› distribution. So if you have a poor hand, but with some support fo partner's› suit, then rebid his suit at the next level, for example, 1D-2D.››If you have a good hand, perhaps an opening bid in your own right, then jump›respond, showing your points as well as your strong suit. (For example 1D-2S, -›jumping past 1S.) You have to use your sense here, because there are many›variations.››Another example. Suppose the opening bid was 1NT. You have a poor hand but a›five-card suit. So respond with 2 in that suit - say, 1NT-2S.››Your partner will probably not bid further, because this is assumed to be a›limiting-bid.››If you have a very strong hand, then jump to the level you think best describes›that - but if you bid too high you may not leave room for "slam" bidding.››--------------------------------------------------------------------------------›After 2D, 2H, 2S, 2NT›--------------------------------------------------------------------------------›If partner has bid this, he has a very strong hand. The chances are that you›will have a weak hand, but of course you must respond.››If you have a poor hand, merely support your partner by bidding the next bid up,›say, 2D-2H.››If you hold 6 points or more, bid your best suit at a higher level, such as›2D-3H. Other variations are possible.››--------------------------------------------------------------------------------›After 3C, 3D, 3H, 3S pre-empts›--------------------------------------------------------------------------------›The computer has quite a complex function to respond to your pre-empt, but how›do you respond to it? In general, a pre-empt means "not many points, but one›strong suit".››Therefore you are wise not to change suits unless your hand is exceptionally›strong in another suit. Another consideration is that if you hold 11 point or›less the opposition will probably hold the majority of the points.››You are probably best to bid "P" (pass) in that case. Otherwise, bid higher in›your partners suit, say 3D-4D.››Bidding to slam. This can be tricky (pardon the pun). If you wish to bid to slam›(6 or 6 'something'), signal this by bidding '4C'. The computer will probably›assume you are asking for aces, and will respond:›› 4D - 0 aces› 4H - 1 ace› 4S - 2 aces› 4NT- 3 aces› 5C - 4 aces››You should next ask for kings. Do this by bidding the next available bid. For›example, if the computer has responded 4S, you return 4NT. The computer will›tell you how many kings it has by bidding like this:››* Next available bid, -0 kings›* Next available bid +1, -1 king›* Next available bid +2, -2 kings, and so on.››For example, if you had asked for kings by bidding 4NT (as above), the computer›will bid 5H if it holds 2 kings.››Armed with knowledge of top cards, you can then make your final bid.››The problem comes when the computer bids 4C. Does this mean it is asking you for›aces? You have to infer this from the pattern of the previous bidding.››Bidding after opening-bid and response. The object is to bid the best possible›suit, or NT if a good fit cannot be found, at the highest level that you think›the cards can be played.››Generally, after opening-bid and response, you should have a good idea of point›counts and distribution, and you should bid naturally for best effect.››Interference and competitive bidding. The same rules apply as before, except›that you may not be in a position to give a clear, unambiguous description of›your hand.››Doubling. The computer thinks of 'double' as an indication of strength. It will›not double for penalty points.›