Saturday, March 22, 2003
M I N D  G A M E S

Money game
Aditya Rishi

We only think when confronted with a problem.
John Dewey

TWO cricket commentators, who call each other Kris and Sherry, are sitting outside television studios in South Africa, with faces of openers who have just got out on zero together on the first ball of the match. Kris, senior partner at the crease, struggles to find words of encouragement for Sherry, but his mind is "abzalutely" blank.

"Cheeka Bhai, I can barely walk, with both my feet in my mouth, but, while this is usual for me, I fail to understand how you fell into the same trap," says Sherry. Cheeka (Kris): "I never imagined I'd have to face a Royal Bengal Tiger in South Africa. No one, now, want us for comments on such wild big shots." Sherry: "When I got out in the middle that way, I would change my game. Let's pick up some other game." Cheeka: "It's a bright idea, but, which game should we pick?" Sherry: "The tournament guidebook says: when in doubt consult Duckworth-Lewis." The former cricketers, then, approach Duckworth and Lewis, famous mathematicians.


Sherry and Kris: "Give us a game that has some money in it." Duckworth and Lewis: "In 1976, in his book 'On Numbers and Games', John Conway gave the description of a mathematical game 'money strip' that resembled the ancient game of coin strip. It can be twisted in many ways to come up with new, even more exciting games."

"For playing this game, you'd need: - 1. A strip of paper, any length, marked off into squares in a series; 2. Some markers - a bunch of coins or scraps of paper. Since the winner gets all of the markers, coins would be fun to use; 3. A small cup that can serve as the moneybag. It must be large enough to hold all the coins."

"To play, set up the game by laying out the strip of paper and placing any number of markers or coins anywhere on the paper. More than one coin may occupy a square, and any number of squares may be empty. The moneybag is placed to the left of the paper strip. Each player takes turns moving markers. The rules for moving these are as follows: Only one marker at a time can be moved. Any number of markers can share a square, so, you can move a marker to a square that is occupied, but not past it. No marker may pass another marker on a turn. However, a marker can land in the same square as another marker. If it happens to move ahead on the next turn, that doesn't count as passing. Markers only move to the left. The moneybag counts as a 'square' and markers can be placed in it, too. Within these restrictions, markers can be moved any number of squares. The person who drops the last marker in the moneybag is the winner and gets to keep them all." While Kris and Sherry come out as confused as before, the professors say to each other: "Dekha, bhagaa diya na." (Write at The Tribune or