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DEFINT A-ZDECLARE FUNCTION openlist% (filename AS STRING)DECLARE FUNCTION wordIndex% (myWord AS STRING)REDIM SHARED wordLst(0) AS STRING * 5DIM user AS STRING, id AS INTEGERPRINT "Loading list..."IF (NOT openlist%("words.dat")) THEN PRINT "Something went wrong": END' picking a random word from the list...PRINT "picking a random word: "; CHR$(34); wordLst(INT(RND * (UBOUND(wordLst) + 1))); CHR$(34)' testing user input (only accept existing words)DO  INPUT "Guess a word:", user  IF LEN(user) THEN    id = wordIndex%(user)    IF (id < 0) THEN      PRINT "This word is not in the dictionary"    ELSE      PRINT "This word is index #"; id    END IF  ELSE    EXIT DO  END IFLOOP' Open word list. The list MUST be formatted and orderly; if not, the routine' will handle that for you and update the file so it loads faster next time.' Users can add (or remove) words from the list. In a perfect world, we should' make sure there's enough memory available to store the dictionary and also' verify data integrity (so only words with characters in range A-Z are ok'd.)FUNCTION openlist% (filename AS STRING)  DIM ff AS INTEGER, update AS INTEGER, tmp as string * 5  DIM count AS INTEGER, offset AS INTEGER, max AS INTEGER, hiRef AS INTEGER   ' open file  ff = FREEFILE  OPEN filename FOR INPUT AS #ff  ' file size should be multiple of 7 (doesn't guarantee data integrity)  IF (LOF(ff) MOD 7) THEN    CLOSE #ff    EXIT FUNCTION  END IF  ' resize word array  REDIM wordLst(LOF(ff) \ 7 - 1) AS STRING * 5  ' store all in uppercase, then close file  FOR i% = 0 TO UBOUND(wordLst)    INPUT #ff, tmp    wordLst(i%) = ucase$(tmp)  NEXT i%  CLOSE #ff  ' now make sure they are alphabetically sorted, this can take a while  ' depending on the number of words and how disorderly the list is.  count = UBOUND(wordLst) + 1  offset = count \ 2  DO WHILE offset    max = count - offset - 1    DO      hiRef = 0      FOR i% = 0 TO max        IF (wordLst(i%) > wordLst(i% + offset)) THEN          SWAP wordLst(i%), wordLst(i% + offset)          update = -1          hiRef = i%        END IF      NEXT i%      max = hiRef - offset    LOOP WHILE hiRef    offset = offset \ 2  LOOP  ' list had to be sorted, re-save so it loads faster next time  IF update THEN    OPEN filename FOR OUTPUT AS #ff    FOR i% = 0 TO UBOUND(wordLst)      PRINT #ff, wordLst(i%)    NEXT i%    CLOSE #ff  END IF  ' all done  openlist% = -1END FUNCTION' Binary search. It's much faster than a linear search (one entry after the' other) but it requires the array to be alphabetically ordered. This function' returns the index of the word within the wordLst() array. If the word cannot' be found, this function returns -1.FUNCTION wordIndex% (myWord AS STRING)  DIM search AS STRING, cueLo AS INTEGER, cueHi AS INTEGER, cueMid AS INTEGER  search = UCASE$(myWord) ' make sure the input is formatted  cueHi = UBOUND(wordLst) ' upper boundary  wordIndex% = -1         ' assume the word doesn't exist  DO WHILE (cueLo <= cueHi)    cueMid = (cueLo + cueHi) \ 2 ' test central word    SELECT CASE wordLst(cueMid)    CASE IS < search      cueLo = cueMid + 1 ' word must be in the 2nd half    CASE IS > search      cueHi = cueMid - 1 ' word must be in the 1st half    CASE ELSE      wordIndex% = cueMid ' found it!      EXIT FUNCTION    END SELECT  LOOPEND FUNCTION