WORD FOR WORD (TM) Copyright 1993 by Richard P. Cember; all rights reserved. Patent pending. Your comments and suggestions in regard to WORD FOR WORD are welcome and desired. Please write to Richard Cember, 1415 Dwyce Drive, Austin, Texas 78757; call at 512-451-0636; or send e-mail to Compuserve ID 73322,1770. NOTE: It is suggested that you use your favorite word processor to format and print this document so you can read it while the game program is up and running. Hardware requirements: WORD FOR WORD will run on any IBM-compatible PC, but a 486 is recommended. Monochrome or color monitors will do, as will black-and-white monitors that display gray scales as a substitute for color. Monochrome monitors will not, however, give you the full benefit of the on-screen color coding (see below) for different classes of words. For processors below the 486, the situation is as follows: A 386 will run the three- and four-letter games very well, but some people may find the five-letter game a little slow. A 286 will run the three-letter game handily, but the five-letter game will definitely run too slowly for comfort, with the four-letter game being somewhere in between. An 8086 will run the program but will certainly be too slow for the four- and five-letter games; I'm not sure whether it will run the three-letter game fast enough to be usable, but I think it will. About WORD FOR WORD: WORD FOR WORD is a game of word puzzles and strategy for two or more human beings. The object of the game is to solve your WORD FOR WORD puzzle, while blocking other players from solving theirs. The winner is the first player to solve his (or her) WORD FOR WORD puzzle, or the last player left after all other players have been completely blocked from a solution to their WORD FOR WORD puzzles. The game is played on a computer. A brief history of WORD FOR WORD puzzles: The puzzles referred to here as WORD FOR WORD puzzles were first invented by Lewis Carroll in 1879. Carroll called them "Doublets", and they made their first appearance in the magazine "Vanity Fair" that same year. Carroll's complex scoring system has been long ignored, but the puzzles have remained popular ever since their introduction, under many names in addition to "Doublets" ("word ladders", "word golf", etc.). Most modern devotees of Doublets are not aware that Carroll, in 1892, introduced a modified version of the Doublets puzzle in which anagrams (see below) are permitted, as well as single-letter substitutions. This modification vastly increases the number of possible puzzles and solutions. The WORD FOR WORD puzzle is the 1892 version of Doublets. Rex Games, Inc. (San Francisco, California) publishes a Doublets game (a card game, not software!) called WORD TREK, which contains many interesting 1892-type Doublets puzzles written in a style quite different from Lewis Carroll's own. To solve WORD FOR WORD puzzles: Two words with the same number of letters make a WORD FOR WORD puzzle. The solution to the puzzle is a sequence of words that connects the first puzzle word to the second puzzle word. Each word in the sequence is related to the word before it in one of two ways: each word is either (1) made up of the same letters in a different order (i.e., is an anagram of the word preceding it), or (2) is identical to the word preceding it, except for the change of a single letter. One WORD FOR WORD puzzle may have many different solutions, and different solutions may contain different numbers of steps. Here is a simple example of a three-letter WORD FOR WORD puzzle: OPT TIP. One possible solution for the puzzle OPT TIP is: OPT, TOP, TIP. This solution is achieved by first changing OPT to TOP, through rearrangement of the letters of OPT; then changing TOP to TIP, by replacing O with I. A more interesting example is the four-letter puzzle TONE POEM. One solution using four intermediate steps is: tone, pone, pore, port, poet, poem. An alternative, shorter solution, using two intermediate steps is: tone, pone, pome, poem. Many other solutions to TONE POEM exist. Acceptable words are those which are not proper nouns (names of people, places or things, normally capitalized), abbreviations, contractions, hyphenations, or foreign words that have not been absorbed into English. You can solve WORD FOR WORD puzzles by purely mental activity; however, for all but the simplest puzzles it is much easier if you use a pencil and paper. If you've never played WORD FOR WORD before, it is strongly suggested that you do a few three-letter or four-letter WORD FOR WORD puzzles to "get the hang of it" before you play your first game of WORD FOR WORD. It may seem a little puzzling at first, but you will get it very quickly! Once you've got the hang of the word puzzles, the formal rules of the game will be easy to understand. Here are a few practice puzzles; for solutions, see the file SOLUSHNS.TXT: 1. red sky 2. fire sale 3. hard rock 4. call home 5. pear tree 6. truck plaza 7. sugar maple (Numbers 6 and 7 are hard ones.) Overview of the game (see the file RULES.TXT for the full rules of the game): WORD FOR WORD is a game for two or more human players. Players sit down together in front of the computer, each with pencil and paper. (A laptop computer is most convenient, as it may easily be placed on a coffee table or a conference table, but a desktop computer will do.) At the beginning of the game, the players decide whether they will play a game of three-, four-, or five-letter words. Each player receives a WORD FOR WORD puzzle selected by the computer. All the players' puzzles have one word in common, while the other word of each player's puzzle is unique to that player. Each player's puzzle is displayed beneath and to the left of that player's name. After an opening period, during which players study their own and their opponents' puzzles, moves begin. Players make their moves in turns. With each move, a player either saves a word, deletes a word, attempts to clinch a victory, or attempts to force a draw. A saved or deleted word may be any acceptable English word. If a player deletes a word, it means that no one can use that word to solve his or her puzzle. ("His or her" is abbreviated hereafter as "his", "he or she" as "he".) If a player saves a word, it means that no one can thereafter delete that word. A player is eliminated from the game when a deletion makes the solution of his puzzle impossible. A player wins when he recognizes that a solution to his puzzle can be assembled from among the saved words. A player may also win by the elimination of all other players. Under certain circumstances, a player in a two-player game can force a draw. The computer guides the game by prompting the players for moves, then recording and displaying them. After each deletion the computer determines whether any player has been eliminated because his puzzle no longer has a solution. Beneath each player's name on the game board are posted that player's saves and deletions. (The posting of these words begins somewhat left of the player's name so that, if the game becomes a lengthy one, more than one column is available to post each player's words.) Each player's puzzle words, which are automatically considered as saved words, are highlighted and displayed beneath his name. On a color screen the puzzle words are highlighted in blue; on a black-and-white screen, the puzzle words are highlighted in white. On both kinds of screen, saved words are recorded for each player in white in the order in which they occur, while deletions are recorded for each player in light blue in the order in which they occur. An arrow marks the last save or deletion that was made. The game program may be interrupted at any time by pressing ctrl-C. When the game is over: After the last move of the game you will have the opportunity to view various "optimal" solutions of the players' puzzles. An optimal solution is a solution (not necessarily unique) composed of the fewest possible steps. An "optimal solution given the current deletions" is one that has as few steps as possible at the time the game ended, with certain words (the deletions) not available. A solution that is "globally optimal" is one that has as few steps as possible using the complete word lists, without regard to deletions. A note on the composition of the word lists: I put these word lists together from various sources of words, then went through them by hand to eliminate unacceptable words, as well as to remove profanity and ethnic slurs. (Linguistic purists: sorry, but I can't afford to leave that stuff in.) The result should correspond pretty much to a "college" dictionary. The word lists are in ASCII so that you can modify them if you want to, but if you pass this program to someone else please pass only the original word lists. If you find a word that you believe is unacceptable please let me know. Now go to the rules (RULES.TXT).