Bulls and Cows (also known as Cows and Bulls or Pigs and Bulls) is a
code
In communications and information processing, code is a system of rules to convert information—such as a letter, word, sound, image, or gesture—into another form, sometimes shortened or secret, for communication through a communicati ...
-breaking mind or
paper and pencil game
Paper-and-pencil games or paper-and-pen games (or some variation on those terms) are games that can be played solely with paper and pencils (or other writing implements), usually without erasing. They may be played to pass the time, as iceb ...
for two or more players, predating the commercially marketed
board game
Board games are tabletop games that typically use . These pieces are moved or placed on a pre-marked board (playing surface) and often include elements of table, card, role-playing, and miniatures games as well.
Many board games feature a co ...
''
Mastermind'' and the hit word game
Wordle.
The game is played in turns by two opponents who aim to decipher the other's secret code by
trial and error.
The numerical version
The numerical version of the game is usually played with 4 digits, but can be played with any number of digits.
On a sheet of paper, the players each write a 4-digit secret number. The digits must be all different. Then, in turn, the players try to guess their opponent's number who gives the number of matches. The digits of the number guessed also must all be different. If the matching digits are in their right positions, they are "bulls", if in different positions, they are "cows". Example:
*Secret number: 4271
*Opponent's try: 1234
*Answer: 1 bull and 2 cows. (The bull is "2", the cows are "4" and "1".)
The first player to reveal the other's secret number wins the game.
The game may also be played by two teams of players, with the team members discussing their strategy before selecting a move.
Computer versions of the game starting appearing on mainframes in the 1970s. One version called BASIC MOO was published in the DECUS Program Library for
PDP computers and another was available through the DEC Users Society, both dating from 1971. In 1972, a version was written for the
Multics
Multics ("Multiplexed Information and Computing Service") is an influential early time-sharing operating system based on the concept of a single-level memory.Dennis M. Ritchie, "The Evolution of the Unix Time-sharing System", Communications of ...
operating system at MIT. A version written by Lane Hauck in the language
FOCAL for the
PDP-8
The PDP-8 is a 12-bit minicomputer that was produced by Digital Equipment Corporation (DEC). It was the first commercially successful minicomputer, with over 50,000 units being sold over the model's lifetime. Its basic design follows the pioneer ...
later served as the basis for the handheld game Comp IV by
Milton Bradley
Milton Bradley (November 8, 1836 – May 30, 1911) was an American business magnate, game pioneer and publisher, credited by many with launching the board game industry, with his eponymous enterprise, which was purchased by Hasbro in 1984, and ...
.
These programs maintained a league table of players' scores, and protecting the integrity of this league table became a popular case study for researchers into computer security. Because the game has simple rules while still being difficult and entertaining, there are many computer variants; it is often included on cellphones and PDAs.
It is proved that any number can be solved within seven turns. The average minimal game length is turns.
The word version
This version is usually played orally, but is easier to play if each player (or each team) keeps written notes. It is exactly like the numerical version, except instead of 4-digit numbers, 4-letter words are used. They must be real words, according to whatever language or languages you are playing the game in. Alternative versions of the game can be played with 3-letter or 5-letter words, but the 4-letter version remains the most popular one.
The game play for the word version is as follows.
*One player (the Host) thinks of an
isogram word (i.e. no letter appears twice) and, if the word length is not pre-determined, announces the number of letters in the word.
*Other players (the Guessers) try to figure out that word by guessing isogram words containing the same number of letters.
*The Host responds with the number of Cows & Bulls for each guessed word. As with the digit version, "Cow" means a letter in the wrong position and "Bull" means a letter in the right position.
For example, if the secret word is HEAT, a guess of COIN would result in "0 Bulls, 0 Cows" (none of the guessed letters are present); a guess of EATS would result in "0 Bulls, 3 Cows" (since E, A, T are all present, but in the wrong positions from the guess), and a guess of TEAL would result in "2 Bulls, 1 Cow" (since E and A are in the right positions, while T is in the wrong position). The game continues until one of the Guessers scores "4 Bulls" for guessing HEAT exactly.
The word version of Bulls and Cows was later adapted to
Wordle, a
web-based word game
Word games (also called word game puzzles or word search games) are spoken, board, or video games often designed to test ability with language or to explore its properties.
Word games are generally used as a source of entertainment, but can ...
released in 2021 which almost immediately became a popular social media sensation. Players have six attempts to guess a five-letter word.
See also
*
Jotto {{Short description, Logic-oriented word game
Jotto (or Giotto) is a logic-oriented word game played with two players, a writing implement, and a piece of paper with the alphabet on it. Each player writes a secret word and attempts to guess the oth ...
, a similar game with words
*
''Lingo'' (American game show), a game show that contains word puzzles with similar gameplay
*
Sudoku
Sudoku (; ja, 数独, sūdoku, digit-single; originally called Number Place) is a logic-based, combinatorial number-placement puzzle. In classic Sudoku, the objective is to fill a 9 × 9 grid with digits so that each column, each row ...
*
''Wordle'' (video game), an adaptive online game, with 5 letter words
*
''Mastermind'' (board game), an adaptive game using coloured pegs
References
External links
Page with the PL/1 code for Moo by J.M. Grochow* {{cite journal , last1=Knuth , first1=D. E. , title=The Computer as a Master Mind , journal=J. Recr. Math. , date=1976–1977 , volume=9 , pages=1–6 , url=http://www.cs.uni.edu/~wallingf/teaching/cs3530/resources/knuth-mastermind.pdf , access-date= , archive-url=https://web.archive.org/web/20170211044050/http://www.cs.uni.edu/~wallingf/teaching/cs3530/resources/knuth-mastermind.pdf , archive-date=11 February 2017
Bulls and Cows online solveriOS version of Bulls & CowsCowBull
a web version of Bulls & Cows
Koalas
a similar online game with cute animals
Games of mental skill
Guessing games
Logic puzzles
Paper-and-pencil games