Bulls and Cows
Posted: 29 Jul 2015, 08:16
Here's an old game that might be familiar to some of you, either the original pencil-and-paper version or the commercial version known as "Master Mind" or "Mastermind". I've adapted it slightly for forum play.
One player chooses a secret four-digit number, which may begin with 0. (To keep it simple initially, I suggest that all four digits should be different.) The other players take it in turns to try to guess the number. For each guess, the first player gives the number of matches as follows: if a digit matches and is in the right position, it scores one "bull"; if it matches but is in the wrong position, it scores one "cow". For example:
Secret number: 3674
Guess: 5637
Answer: 1 bull and 2 cows
(The bull is "6", the cows are "3" and "7".)
The other players have up to 10 guesses between them. A player who guesses the number correctly gets to set the next number. If no player does so within 10 guesses, the first player sets again.
A player may not have two guesses in a row, unless he or she believes the second guess is the right answer. If it turns out to be wrong then that player cannot guess again in that game.
If it turns out that the first player has given a wrong answer at any point, the game is void and any other player can start a new one.
Clear? If there are no questions, I'll set the first number.
One player chooses a secret four-digit number, which may begin with 0. (To keep it simple initially, I suggest that all four digits should be different.) The other players take it in turns to try to guess the number. For each guess, the first player gives the number of matches as follows: if a digit matches and is in the right position, it scores one "bull"; if it matches but is in the wrong position, it scores one "cow". For example:
Secret number: 3674
Guess: 5637
Answer: 1 bull and 2 cows
(The bull is "6", the cows are "3" and "7".)
The other players have up to 10 guesses between them. A player who guesses the number correctly gets to set the next number. If no player does so within 10 guesses, the first player sets again.
A player may not have two guesses in a row, unless he or she believes the second guess is the right answer. If it turns out to be wrong then that player cannot guess again in that game.
If it turns out that the first player has given a wrong answer at any point, the game is void and any other player can start a new one.
Clear? If there are no questions, I'll set the first number.