5 REM **** WRITTEN BY ERIC PETERS, DIGITAL 10 REM *** CONVERTED TO RSTS/E BY DAVID AHL, DIGITAL 70 PRINT "LUNAR LANDING SIMULATION" 80 PRINT "----- ------- ----------"\PRINT 100 INPUT "DO YOU WANT INSTRUCTIONS (YES OR NO)";A$ 120 IF A$="NO" THEN 390 160 PRINT 200 PRINT "YOU ARE LANDING ON THE MOON AND HAVE TAKEN OVER MANUAL" 210 PRINT "CONTROL 500 FEET ABOVE A GOOD LANDING SPOT. YOU HAVE A" 220 PRINT "DOWNWARD VELOCITY OF 50 FT/SEC. 120 UNITS OF FUEL REMAIN." 225 PRINT 230 PRINT "HERE ARE THE RULES THAT GOVERN YOUR SPACE VEHICLE:" 240 PRINT "(1) AFTER EACH SECOND, THE HEIGHT, VELOCITY, AND REMAINING" 250 PRINT " FUEL WILL BE REPORTED." 260 PRINT "(2) AFTER THE REPORT, A '?' WILL BE TYPED. ENTER THE" 270 PRINT " NUMBER OF UNITS OF FUEL YOU WISH TO BURN DURING THE" 280 PRINT " NEXT SECOND. EACH UNIT OF FUEL WILL SLOW YOUR DESCENT" 290 PRINT " BY 1 FT/SEC." 310 PRINT "(3) THE MAXIMUM THRUST OF YOUR ENGINE IS 30 FT/SEC/SEC OR" 320 PRINT " 30 UNITS OF FUEL PER SECOND." 330 PRINT "(4) WHEN YOU CONTACT THE LUNAR SURFACE, YOUR DESCENT ENGINE" 340 PRINT " WILL AUTOMATICALLY CUT OFF AND YOU WILL BE GIVEN A" 350 PRINT " REPORT OF YOUR LANDING SPEED AND REMAINING FUEL." 360 PRINT "(5) IF YOU RUN OUT OF FUEL, THE '?' WILL NO LONGER APPEAR," 370 PRINT " BUT YOUR SECOND BY SECOND REPORT WILL CONTINUE UNTIL" 380 PRINT " YOU CONTACT THE LUNAR SURFACE."\PRINT 390 PRINT "BEGINNING LANDING PROCEDURE....."\PRINT 410 PRINT "G O O D L U C K ! ! !" 420 PRINT\PRINT 440 PRINT "SEC FEET SPEED FUEL PLOT OF DISTANCE" 450 PRINT 455 T=0\H=500\V=50\F=120 490 PRINT T;TAB(4);H;TAB(12);V;TAB(20);F;TAB(29);"I";TAB(H/12+29);"*" 500 INPUT B 510 IF B<0 THEN 650 520 IF B>30 THEN B=30 530 IF B>F THEN B=F 540 V1=V-B+5 560 F=F-B 570 H=H-.5*(V+V1) 580 IF H<=0 THEN 670 590 T=T+1 600 V=V1 610 IF F>0 THEN 490 615 IF B=0 THEN 640 620 PRINT "*** OUT OF FUEL ***" 640 PRINT T;TAB(4);H;TAB(12);V;TAB(20);F;TAB(29);"I";TAB(H/12+29);"*" 650 B=0 660 GOTO 540 670 PRINT "*** CONTACT ***" 680 H=H+.5*(V+V1) 690 IF B=5 THEN 720 700 D=(-V+SQR(V*V+H*(10-2*B)))/(5-B) 710 GOTO 730 720 D=H/V 730 V1=V+(5-B)*D 760 PRINT "TOUCHDOWN AT";T+D;"SECONDS." 770 PRINT "LANDING VELOCITY =";V1;"FT/SEC" 780 PRINT F;"UNITS OF FUEL REMAINING." 790 IF V1<>0 THEN 810 800 PRINT "CONGRATULATIONS!! A PERFECT LANDING!" 805 PRINT "YOUR LICENSE WILL BE RENEWED.......LATER." 810 IF ABS(V1)<2 THEN 840 820 PRINT "***** SORRY, BUT YOU BLEW IT!!!!" 830 PRINT "APPROPRIATE CONDOLENCES WILL BE SENT TO YOUR NEXT OF KIN." 840 PRINT\PRINT\PRINT 850 INPUT "ANOTHER MISSION";A$ 870 IF A$="YES" THEN 390 880 PRINT\PRINT "CONTROL OUT."\PRINT 999 END