## Thursday, November 19, 2009

### Precognition -- Card Game

This is a card game for a plural number of players.

First, the cards from a standard deck (no jokers) are dealt face-down to the players, so that each player has the same number of cards.

The players then each examine the hand they have been dealt, keeping their cards secret from the other players. (Of course, if there are two players, you know the cards your opponent has are exactly those cards you don't have.) :)

All that matters in this game as far as the cards are concerned are their numerical values. (Ace = 1, Jack = 11, Queen = 12, King = 13.)

The players each secretly on their own piece of paper write down a series of letters ("U" for up, "D" for down, "S" for stay), corresponding to a predicted outcome. (See below.) The players can write down any number of these letters they each choose -- 1 letter, up to a string of letters of length equal to the number of cards.

Next, the players take turns placing cards face-up, one card per move, making a single row of cards on the table between the players. The cards are placed in the row from the left to the right. (I suggest that each card be placed on top of the card below it, being placed a little to the right so that the value of each card is showing.)

After all cards are placed in the row, the players reveal their lists of letters.

Consider the "changes" between consecutive numbers in the row of cards. Either a number goes up (U) from the previous number in the row, goes down (D), or stays the same (S). Form a list of these changes written in order from left to right.
The winner is the player with the longest string of letters that corresponds to any subset of consecutive changes within the row of cards.

For example, if we have the (short) row of cards:

2,6,5,4,7,9,7,1,2,2,5,8

And a player has "UUDDUSU",
then this corresponds to:
2,6,5,(4,7,9,7,1,2,2,5),8

because 4 to 7 is U (up), 7 to 9 is U, 9 to 7 is D (down), 7 to 1 is D, 1 to 2 is U, 2 to 2 is S (stay), and 2 to 5 is U.

If this is the longest matching string (7 letters) of U's, D's and S's by any player, then this player wins.

(Note: A player can almost always get a match, for example, by having a string of one letter U or D. But then there is a good chance someone else will have a longer matching string.)

If there are a number of players that all tied for first place, then these players play again amongst themselves as many games as necessary, eliminating players each round, so as to determine a final champion.

Thanks,
Leroy Quet