SUBROUTINE LEFTY
      IMPLICIT INTEGER(A - Z)
C
C	THIS SUBROUTINE CONTROLS THE MOTION OF LEFTY.  LEFTY MOVES
C	AT 92% OF TOP SPEED, BUT DOES NOT FOLLOW PACMAN VERY WELL.
C	ON EARLY BOARDS, HE ONLY CHANGES DIRECTION WHEN HE 'SEES' PACMAN.
C
C
C	VT100 DISPLAY CONTROL PARAMETER DEFINITIONS
C
CCURSOR POSITION REPORT
CCURSOR UP
CCURSOR DOWN
CCURSOR FORWARD
CCURSOR BACK
CDOUBLE WIDTH LINE
      PARAMETER CUP = 1, CUU = 2, CUD = 3, CUF = 4, CUB = 5, DECDWL = 6,
     * DECDHL = 7, DECRC = 8, DECSC = 9, DECSWL = 10, ED = 11, EL = 12, 
     *SGR = 13, NEL = 14, SCS = 15, SM = 16, RM = 17, ANSI = 18, CPP=19
C MAZE DIMENSIONS
      PARAMETER RMAR = 24, CMAR = 53
C BIT SETTINGS FOR DIRECTIONALS AND MSTATE TABLE
      PARAMETER HALT = 0, UP = 1, DOWN = 2, LEFT = 4, RIGHT = 8
	PARAMETER DOT=16, EGZ=32, TUNNEL=64, DECISN="200
	PARAMETER SHFIN="17, SHFOUT="16, SPACE="40
C DISPLAYABLE CHARACTERS
	PARAMETER PMAN="52, EGZCHR="146, DOTCHR="176, TUNCHR="137
C BOARD STATE
      PARAMETER GOOD = 1, BAD = 2, BLINK = 3, EATEN = 4
C QIO FUNCTION CODES
	PARAMETER IOWVB="11000
C
      INTEGER*4SCORE, TIMER, STATIM, LTIM, CTIM, FTIM, NTIM, FRUON, FRUO
     *FF
      INTEGER*2PRL(6), EATSCO(4), FRUSCO(6), FRUDSR(20), FRUDSC(20)
      BYTE LMAN(3), CMAN(3), FMAN(3), NMAN(3), EATCHR(4), FRUCHR(6)
      BYTE MSTATE(CMAR, RMAR), MOVE(24, 9), FRUTBL(20)
C COMMONS
      COMMON/MSTCOM/MSTATE
      COMMON/PACCOM/FDIR, NDIR, LDIR, CDIR, CYCLE, MOVE, SCORE, DOTCNT, 
     *COL, ROW, LCOL, LROW, CCOL, CROW, FCOL, FROW, NCOL, NROW, CYCTIM, 
     *TIMER, BOARD, STATE, STATIM, LTIM, CTIM, FTIM, NTIM, LPRISN, CPRIS
     *N, FPRISN, NPRISN, LPRISR, LPRISC, CPRISR, CPRISC, FPRISR, FPRISC,
     * NPRISR, NPRISC, RDOOR, CDOOR, PRITIM, GOODTM, BLNKTM, EATCNT, EAT
     *CHR, EATSCO, EXTRA, LMAN, CMAN, FMAN, NMAN, PACCNT, INIROW, INICOL
     *, GAMOVR, FRUIT, FRUTIM, FRULTH, FRUON, FRUOFF, FRUSCO, FRUCHR, FR
     *UCOL, FRUROW, FRUCNT, FRUDSR, FRUDSC, PRL, FRUTBL, PACDSC, PACDSR,
     * PACDSD, FRUBRD
      OLDDIR = LDIR
      IF (.NOT.(LPRISN .EQ. 1)) GOTO 2000
CIF IN PRISON...
        IF (.NOT.(STATE .NE. BAD)) GOTO 2020
CDONT ESCAPE WHILE PACMAN
CIS EATING
          RETURN
2020    CONTINUE
        IF (.NOT.(LTIM+PRITIM .LE. TIMER)) GOTO 2040
CIF TIME TO GET OUT,
CERASE LEFTY FROM PRISON
          CALL UVT100(CPP, LPRISR, LPRISC, SPACE)
          LROW = RDOOR
          LCOL = CDOOR
CMOVE HIM TO PRISON DOOR
          CALL UVT100(CPP, LROW, LCOL, LMAN(STATE))
CNO LONGER IN PRISON
          LPRISN = 0
CNO MOTION YET
          LDIR = HALT
CNOT YET TIME TO GET OUT
          GOTO 2050
2040    CONTINUE
          RETURN
2050    CONTINUE
C
C	IF PACMAN IS IN EATING MOOD (STATE IS 'GOOD' OR 'BLINK'),
C	ALL MONSTERS MOVE AT 67% OF TOP SPEED. TEST FOR THIS CONDITION.
C
2000  CONTINUE
      IF (.NOT.(STATE .NE. BAD.AND.MOVE(CYCLE, 9) .EQ. 0)) GOTO 2060
        LDIR = OLDDIR
        RETURN
C
C	IF THIS IS A TUNNEL LOCATION, TEST IF MOTION ALLOWED THIS CYCLE
C
2060  CONTINUE
      IF (.NOT.(TSTBIT(MSTATE(LCOL, LROW), TUNNEL) .EQ. 1)) GOTO 2080
        IF (.NOT.(MOVE(CYCLE, 3) .EQ. 0)) GOTO 2100
          LDIR = OLDDIR
          RETURN
2100    CONTINUE
C
C	ELSE IF THIS IS A DECISION BIT, AND THE PACMAN IS ON THE SAME ROW
C	OR COLUMN AS WE ARE, CALL DECIDE TO SEE IF WE CHANGE DIRECTION.
C	(AFTER THE SECOND BOARD ALSO CALL DECIDE 50% OF THE TIME, AND
C	AFTER THE FOURTH BOARD, CALL DECIDE 67% OF THE TIME).
C
        GOTO 2090
2080  CONTINUE
      IF (.NOT.(TSTBIT(MSTATE(LCOL, LROW), DECISN) .EQ. 1)) GOTO 2120
        IF (.NOT.(LROW .EQ. ROW.OR.LCOL .EQ. COL)) GOTO 2140
          CALL DECIDE(LCOL, LROW, LDIR)
          GOTO 2150
2140    CONTINUE
        IF (.NOT.(BOARD .GT. 2.AND.BOARD .LT. 5.AND.MOVE(CYCLE, 3) .EQ. 
     *1)) GOTO 2160
          CALL DECIDE(LCOL, LROW, LDIR)
          GOTO 2150
2160    CONTINUE
        IF (.NOT.(BOARD .GT. 4.AND.MOVE(CYCLE, 9) .EQ. 1)) GOTO 2180
          CALL DECIDE(LCOL, LROW, LDIR)
2180    CONTINUE
2150    CONTINUE
C
C	IF WE HAVE RUN INTO A WALL, FIND A NEW DIRECTION
C
2120  CONTINUE
2090  CONTINUE
      IF (.NOT.(TSTBIT(MSTATE(LCOL, LROW), LDIR) .EQ. 0)) GOTO 2200
        CALL WALL(LCOL, LROW, LDIR)
C
C	IF MOTION IS PROHIBITED THIS CYCLE, RESET OLD DIRECTION AND RETURN
C
2200  CONTINUE
      IF (.NOT.(MOVE(CYCLE, LDIR) .EQ. 0.OR.MOVE(CYCLE, 5) .EQ. 0)) GOTO
     * 2220
        LDIR = OLDDIR
        RETURN
C
C	ALL READY TO MOVE
C
2220  CONTINUE
CCURSOR TO CURRENT LOCATION
      IF (.NOT.(TSTBIT(MSTATE(LCOL, LROW), DOT) .EQ. 1)) GOTO 2240
        CALL UVT100(CPP, LROW, LCOL, DOTCHR)
CREWRITE DOT
        GOTO 2250
2240  CONTINUE
      IF (.NOT.(TSTBIT(MSTATE(LCOL, LROW), EGZ) .EQ. 1)) GOTO 2260
        CALL UVT100(CPP, LROW, LCOL, EGZCHR)
CREWRITE ENERGIZER
        GOTO 2250
2260  CONTINUE
      IF (.NOT.(FRUIT .EQ. 1.AND.LCOL .EQ. FRUCOL.AND.LROW .EQ. FRUROW))
     * GOTO 2280
        CALL UVT100(CPP, LROW, LCOL, FRUCHR(BOARD))
CREWRITE FRUIT
        GOTO 2250
2280  CONTINUE
        CALL UVT100(CPP, LROW, LCOL, SPACE)
CREWRITE SPACE
2250  CONTINUE
      IF (.NOT.(LDIR .EQ. LEFT)) GOTO 2300
        LCOL = LCOL - 1
        GOTO 2310
2300  CONTINUE
      IF (.NOT.(LDIR .EQ. UP)) GOTO 2320
        LROW = LROW - 1
        GOTO 2310
2320  CONTINUE
      IF (.NOT.(LDIR .EQ. RIGHT)) GOTO 2340
        LCOL = LCOL + 1
        GOTO 2310
2340  CONTINUE
      IF (.NOT.(LDIR .EQ. DOWN)) GOTO 2360
        LROW = LROW + 1
2360  CONTINUE
2310  CONTINUE
      IF (.NOT.(LCOL .GT. CMAR)) GOTO 2380
        LCOL = 1
        GOTO 2390
2380  CONTINUE
      IF (.NOT.(LCOL .LT. 1)) GOTO 2400
        LCOL = CMAR
2400  CONTINUE
2390  CONTINUE
      IF (.NOT.(LROW .GT. RMAR)) GOTO 2420
        LROW = 1
        GOTO 2430
2420  CONTINUE
      IF (.NOT.(LROW .LT. 1)) GOTO 2440
        LROW = RMAR
2440  CONTINUE
2430  CONTINUE
      CALL UVT100(CPP, LROW, LCOL, LMAN(STATE))
CTEST FOR COLLISION
      CALL COLIDE
      RETURN
      END