Sudoku

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This is a simple program to play a sudoku game.

I found a file SUDOKU17.TXT on the Internet which had over 30,000 games and assume you could use it. The program can save and restore a game as "GAME" in whatever file you keep the sudoku text file.

If there is an "H" in the command line, the display is larger.

     PROGRAM SUDOKU

* Public Domain program provided by Keith Robert Johnson

     OPEN 'YOUR.FILE' TO YOUR.FILE ELSE STOP 201,'YOUR.FILE'

     DIM GAME(3)
     EQU THAT TO GAME(1), BASE TO GAME(2), MINE TO GAME(3)

     MAT GAME = ''
     AUTO = @FALSE

     THAT = RND(35396)+1
     READV THAT FROM YOUR.FILE, 'SUDOKU17.TXT', THAT ELSE
        THAT = ' 8   3     7   2 8   5 84  8    9 244       '
        THAT := '192 1    6  52 1   1 2   3     4   7 '
     END
     CONVERT '0' TO ' ' IN THAT
     Z = 0
     FOR Y = 1 TO 9
        FOR X = 1 TO 9
           Z += 1
           BIT = THAT[Z,1]
           IF BIT MATCHES '1N' THEN BASE<1,X,Y> = BIT
        NEXT X
     NEXT Y
     MINE = BASE

START:
* Display the grid
     CRT @(-1)
     CRT @(0,1):
     HUGE = INDEX(@SENTENCE,'H',1)
     IF HUGE THEN
        XSIZ = 19; YSIZ = 37; XREM = 6; YREM = 12
     END ELSE
        XSIZ = 13; YSIZ = 19; XREM = 4; YREM = 6
     END
     FOR X = 1 TO XSIZ
        CRT '  ':
        FOR Y = 1 TO YSIZ
           IF REM(X,XREM) EQ 1 THEN
              IF REM(Y,YREM) EQ 1 THEN CRT '+': ELSE CRT '-':
           END ELSE
              IF REM(Y,YREM) EQ 1 THEN CRT '|': ELSE CRT ' ':
           END
        NEXT Y
        CRT
     NEXT X

     CRT 'Use SEXD to move around, 1-9 to write or 0 to clear number'
     CRT '  C to check position, A to toggle autocheck, Q to quit'
     CRT '  K to keep game, G to get saved game'

* Display the contents
     FOR Y = 1 TO 9
        FOR X = 1 TO 9
           Z += 1
           BIT = MINE<1,X,Y>
           IF HUGE
              THEN CRT @(4*X,2*Y):
              ELSE CRT @(2*X+1,Y+INT((Y+2)/3)):
           IF BIT MATCHES '1N' THEN
              IF BASE<1,X,Y> MATCHES '1N'
                 THEN CRT @(-58):BIT:@(-59):
                 ELSE CRT BIT:
           END ELSE CRT '.':
        NEXT X
     NEXT Y

* Play loop
     X = 1; Y = 1
     LOOP
        IF HUGE
           THEN POSN = @(4*X,2*Y)
           ELSE POSN = @(2*X+1,Y+INT((Y+2)/3))
        CRT POSN:
        THIS = UPCASE(KEYIN())
        CRT @(0,23):@(-4):
     UNTIL THIS EQ 'Q' DO
        LOOP
           INPUT FULL,-1
        WHILE FULL DO
           FULL = KEYIN()
        REPEAT
        CRT POSN:
        BEGIN CASE
           CASE THIS EQ 'A'; AUTO = NOT(AUTO)
           CASE THIS EQ 'S' AND X GT 1 ; X -= 1
           CASE THIS EQ 'D' AND X LT 9 ; X += 1
           CASE THIS EQ 'E' AND Y GT 1 ; Y -= 1
           CASE THIS EQ 'X' AND Y LT 9 ; Y += 1
           CASE THIS EQ 'C' ; GOSUB CHECK
           CASE THIS EQ 'K' ; MATWRITE GAME ON YOUR.FILE,'GAME'
           CASE THIS EQ 'G'
              READ TEST FROM YOUR.FILE,'GAME' THEN
                 MATREAD GAME FROM YOUR.FILE,'GAME' THEN
                    GO START
                 END
              END
              CRT @(0,23):'NO GAME SAVED':
           CASE BASE<1,X,Y> MATCHES '1N' ; CRT CHAR(7):
           CASE THIS EQ '0' OR THIS EQ ' ' ; MINE<1,X,Y> = '' ; CRT '.':
           CASE THIS MATCHES '1N' ; MINE<1,X,Y> = THIS ; CRT THIS:
           CASE 1 ; CRT CHAR(7):
        END CASE
        IF AUTO THEN GOSUB CHECK
     REPEAT
     STOP

CHECK:
     CRT @(0,23):
     GOOD = 'Everything good so far!'
* Check Columns
     THIS = ' Column '
     FOR AA = 1 TO 9
        LINE = ''
        FOR BB = 1 TO 9
           BIT = MINE<1,AA,BB>
           IF BIT NE '' THEN
              IF INDEX(LINE,BIT,1) THEN
                 CRT THIS:AA: ; THIS = ',' ; BB = 99 ; GOOD = ' BAD'
              END ELSE LINE := BIT
           END
        NEXT BB
     NEXT AA

* Check Rows
     THIS = ' Row '
     FOR AA = 1 TO 9
        LINE = ''
        FOR BB = 1 TO 9
           BIT = MINE<1,BB,AA>
           IF BIT NE '' THEN
              IF INDEX(LINE,BIT,1) THEN
                 CRT THIS:AA: ; THIS = ',' ; BB = 99 ; GOOD = ' BAD'
              END ELSE LINE := BIT
           END
        NEXT BB
     NEXT AA

* Check Cells - couldn't figure out an algorithm
     THIS = ' Cell '
     CELL = '1*11,12,13,21,22,23,31,32,33'; GOSUB DOCELL
     CELL = '2*41,42,43,51,52,53,61,62,63'; GOSUB DOCELL
     CELL = '3*71,72,73,81,82,83,91,92,93'; GOSUB DOCELL
     CELL = '4*14,15,16,24,25,26,34,35,36'; GOSUB DOCELL
     CELL = '5*44,45,46,54,55,56,64,65,66'; GOSUB DOCELL
     CELL = '6*74,75,76,84,85,86,94,95,96'; GOSUB DOCELL
     CELL = '7*17,18,19,27,28,29,37,38,39'; GOSUB DOCELL
     CELL = '8*47,48,49,57,58,59,67,68,69'; GOSUB DOCELL
     CELL = '9*77,78,79,87,88,89,97,98,99'; GOSUB DOCELL

     CRT GOOD:
     RETURN

DOCELL:
     ID = CELL[1,1]
     CELL = CELL[3,99]
     CONVERT ',' TO @AM IN CELL
     LINE = ''
     FOR AA = 1 TO 9
        BIT = MINE<1,CELL<AA>[1,1],CELL<AA>[2,1]>
        IF BIT NE '' THEN
           IF INDEX(LINE,BIT,1) THEN
              CRT THIS:ID: ; THIS = ',' ; AA = 99 ; GOOD = ' BAD'
           END ELSE LINE := BIT
        END
     NEXT AA
     RETURN