: stt
 0 4 at ." LUNAR LANDING"
 CR CR ." Jet "
 CR CR ." Vel "
 CR CR ." Ht  "
 CR CR ." Fuel"
 20 0 AT 32 0
 DO
  ." ~"
 LOOP
;

: set
 cls 0 22 at ." HEIGHT"
 20 1
 do
  i 22 at ." __"
  19 i - 1000 *
  .
 loop
 cr stt
;

: ch
 4 j_roll 2 j_pick -
 4 j_roll 4 j_pick -
 4 j_roll 4 j_pick -
 4 + 4 j_roll
;

: pr
 4 0
 do
  i 1+ j_pick i 1+
  2 * 5 at .
  5 spaces
  loop
;

: gr
 3 j_pick 1000 / 19
 swap - 0 max dup
 dup 1+ 18 at space
 1- 18 at space 18
 at ." V"
;

: e1
  7 0 at 3 0
  do
  ."                 "
  cr
 loop
;

: end
 quit
 20 0 at
 begin
  200 100 beep 100 100
  beep 0
 until
;

: ts
 4 j_pick 1 <
 if
  e1 8 2 at ." OUT OF FUEL"
  end
 then
 3 j_pick 1 <
 if
  e1 8 1 at over
  2 <
  if
   ." safe landing"
   end
  then
  ." crash landing"
  end
 then
;

: j_key
 inkey dup
 if
  48 - dup -1 >
  if
   dup 10 <
   if
    swap
   then
  then
 then
 drop
;

: game
 set stt 1500 15000 0
 0
 begin
  3 j_pick 10 / abs
  50 + 75 beep j_key
  ch pr gr ts 0
 until
;

: lunar
 game
;