PROGRAM LANDER
C*************************************************************
C**
C**  STEVE ILLENCIK                  * AFTER MAY 1,1977
C**  C/O REPUBLIC BUILDINGS CORP     *  REPUBLIC BUILDINGS CORP
C**      4010 DUPONT CIRCLE          *  1202 INDUSTRIAL PARK
C**      SUITE 444                   *  VAN WERT, OHIO 45891
C**      LOUISVILLE,KENTUCKY 40207   *
C**                                  *
C**  502-897-7141                    *  419-238-9533
C**
C** LUNER LANDER PROGRAM  VERSION 1.0
C***********************************************************
       COMMON /ALANDS/VELCTY,GRAVTY,RETROR,TMPACT,ALTUDE,FUELR
       COMMON /DRAWER/ITIME,IHIGH,ISCALE
C**********************************************************
       OPEN(UNIT=5,NAME='TO:',CARRIAGECONTROL='NONE')
 10    ITIME = 1
       ISCALE = 1
       IHIGH = 45
       CALL SCREEN
C** GENERATE A RANDOM NUMBER FOR RANDOM SEQUENCE
       TSTRT = SECNDS(0.0)
       IRAND = AMOD(TSTRT,1.0)*100.0
       IRAND = IRAND*2 -1
       GRAVTY = RANDOM(IRAND)*0.009 + 0.003
       RETROR = GRAVTY *  4.00
       TMPACT = RANDOM(IRAND)*20. + 20.
       ALTUDE = RANDOM(IRAND)*15.0 + 20.0
       VELCTY = (ALTUDE - 0.5*GRAVTY*TMPACT**2) / TMPACT
       FUELR = ALTUDE * 4.10 / VELCTY
       GO TO 50
C** SCALING REQUEST
 40    IF(ALTUDE .GT. 8.5)GO TO 42
       IF(ISCALE .EQ. 2)GO TO 100
       ISCALE = 2
       IHIGH  = 9
       GO TO 45
 42    IF(ISCALE .EQ. 1)GO TO 100
       ISCALE = 1
       IHIGH  = 45
 45    ITIME = 1
       CALL SCREEN
 50    CALL CURSOR(11,3,22,30,'INPUT SECONDS TO FIRE ROCKETS ')
       CALL CURSOR(11,33,22,19,'AND FREE FALL TIME ')
       CALL CURSOR(11,65,4,0,' ')
       TYPE 1001,GRAVTY
 1001  FORMAT(F8.3)
 100   CALL REPORT
       IF(ALTUDE .GT. 45.0)GO TO 900
       IF(ALTUDE .LT. 0.1)GO TO 170
       IF(FUELR .LE. 0.0)GO TO 220
       CALL CURSOR(11,52,22,10,'          ')
       CALL CURSOR(11,52,22,0,' ')
       ACCEPT *,RTIME,FTIME
       IF(RTIME .LT. 0.0)GO TO 40
       IF(RTIME .EQ. 999.)GO TO 999
       FUELR = FUELR - RTIME
C** FIND TOTAL GRAVITY TIME
C** ADD FREE FALL TIME AND ROCKET TIME
       GTIME = RTIME + FTIME
       DISTNC = VELCTY*GTIME + 0.5*GRAVTY*GTIME**2 - 0.5*RETROR*FTIME**2
       ALTUDE = ALTUDE - DISTNC
       VELCTY = VELCTY + GRAVTY*GTIME - RETROR*RTIME
       CALL TIMER
       GO TO 100
C** END OF GAME
 170   IX = 7 + (ITIME - 2)*2
       CALL CURSOR(11,IX,20,1,'\')
       CALL CURSOR(11,IX+1,20,1,' ')
       CALL CURSOR(11,IX+2,20,1,'/')
       CALL CURSOR(11,3,22,0,' ')
       CALL CURSOR(12,3,22,0,' ')
       IF(ALTUDE .LT. -0.1)GO TO 200
       IF(ABS(VELCTY) .GT. 0.10)GO TO 200
       IF(VELCTY .LT. 0.05 .AND. VELCTY .GT. -0.05)GO TO 210
       TYPE *,'HARD BUT SAFE LANDING - GOOD JOB'
       GO TO 990
 200   TYPE *,'THE LANDER CRASHED - THERE ARE NO SURVIVORS'
       GO TO 990
 210   TYPE *,'SAFE LANDING - ALL SYSTEMS REPORTED FUNCTIONING'
       GO TO 990
 220   CALL CURSOR(11,3,22,31,'FUEL OUT, LANDER WILL CRASH IN')
       TYPE 1001,FUELR
       CALL CURSOR(11,43,22,7,'SECONDS')
       GO TO 990
 900   TYPE *,'YOU BLASTED OFF THE PLANET - NO HOPE'
 990   TSTRT = SECNDS(0.0)
 995   TIME = SECNDS(TSTRT)
       IF(TIME .GT. 5.)GO TO 10
       GO TO 995
 999   CLOSE(UNIT=5)
       STOP
       END