call clrscr
nf%=1
go% = 1
sv#=0.75
k$ = ""
level% = 1
call title_screen
dim worm%[100]
dim wall%[20]
loop for a% = 1 to 20
  wall%[a%] = 0
endloop
call new_level(level%)
hap% = 1
loop
  wait 0.01
  k$ = key$
  k% = asc%(k$,1)
  if (k% = 37)  and (dir%<>3) then
    dir% = 1
  endif
  if (k% = 38) and (dir%<>4) then
    dir% = 2
  endif
  if (k% = 39) and (dir%<>1) then
    dir%  = 3
  endif
  if (k% = 40) and (dir% <> 2) then
    dir% = 4
  endif
  if k$ = "q" then
    go% = 0
  endif
  if k$ = "r" then
    call drawboard
  endif
  if k$ = "p" then
    dir% = 0
  endif
  if dir% <> 0 then
    call update_worm
  endif
  call draw_block(fx%,fy%)
while go%=1
ENDLOOP
!***************************!
procedure draw_block(bx%,by%)
  call color(3)
  call fillrect(bx% * 2,by%*2,(bx%*2) +2,(by%*2)+2)
endproc
!***************************!
procedure erase_block(bx%,by%)
  call color(0)
  call fillrect(bx% * 2,by%*2,(bx%*2) +2,(by%*2)+2)
endproc
!***************************!
procedure title_screen 
call draw_logo(275,33)
call curpos(20,6)
print "Nibbles for Basice"
call curpos(20,9)
print "Written by Brian Kay in MCMXCVIII"
wx% = 70
loop
  k$ = key$
  wait 0.05
  if wx% < 170 then
    call draw_block(wx%,50)
  endif
  call erase_block(wx%-10,50)
  wx% = wx% + 1
  if wx% = 180 then 
    wx% = 70
  endif
while len%(k$) = 0
endloop
endproc
!***************************!
procedure borders
  call clrscr
  call color(3)
  call fillrect(0,0,480,2)
  call fillrect(0,0,2,190)
  call fillrect(478,0,480,188)
  call fillrect(0,186,479,188)
endproc
!***************************!
procedure drawboard
call borders
loop for a% = 1 to 4
  call fillrect(wall%[((a%-1)*4)+1],wall%[((a%-1)*4)+2],wall%[((a%-1)*4)+3],wall%[((a%-1)*4)+4])
endloop
loop for a% = 1 to wl%
  call draw_block(get_worm(a%,1),get_worm(a%,2))
endloop
endproc
!***************************!
procedure new_level(level%)
  wl% = 10
  hap%=1
  loop for a% = 1 to 100
    worm%[a%] = 0
  endloop
  if level% = 2 then
    call set_wall(1,1,100)
    call set_wall(1,2,100)
    call set_wall(1,3,400)
    call set_wall(1,4,102)
  endif
  if level% = 3 then
    call set_wall(1,1,200)
    call set_wall(1,2,0)
    call set_wall(1,3,202)
    call set_wall(1,4,160)
  endif
  if level% = 4 then
    call set_wall(1,1,200)
    call set_wall(1,2,0)
    call set_wall(1,3,202)
    call set_wall(1,4,160)
    call set_wall(2,1,100)
    call set_wall(2,2,60)
    call set_wall(2,3,102)
    call set_wall(2,4,192)
    call set_wall(3,1,300)
    call set_wall(3,2,60)
    call set_wall(3,3,302)
    call set_wall(3,4,192)
  endif
  if level% = 5 then
    call set_wall(1,1,0)
    call set_wall(1,2,48)
    call set_wall(1,3,240)
    call set_wall(1,4,50)
    call set_wall(2,1,360)
    call set_wall(2,2,0)
    call set_wall(2,3,362)
    call set_wall(2,4,96)
    call set_wall(3,1,240)
    call set_wall(3,2,144)
    call set_wall(3,3,480)
    call set_wall(3,4,146)
    call set_wall(4,1,120)
    call set_wall(4,2,96)
    call set_wall(4,3,122)
    call set_wall(4,4,192)
  endif
  call drawboard
  hx% = 5
  hy% = 6
  dir% = 3
  call disp_food
endproc
!***************************!
procedure update_worm
  if hap% = 1 then tp% = wl%
    else tp% = hap% - 1 endif
  call erase_block(get_worm(tp%,1),get_worm(tp%,2))
  if dir% = 1 then
    hx% = hx% - 1
  endif
  if dir% = 2 then
    hy% = hy% - 1
  endif
  if dir% = 3 then
    hx% = hx%+1
  endif
  if dir% = 4 then
    hy% = hy% + 1
  endif
    if hap% = 1 then hap% = wl%
    else hap% = hap% - 1 endif
    call set_worm(hap%,1,hx%)
    call set_worm(hap%,2,hy%)
    call draw_block(hx%,hy%)
    call check_collision
  return
endproc
!***************************!
procedure get_worm(bl%,xy%)
  bl% = bl% -1
  return(worm%[(bl%*2)+xy%])
endproc
!***************************!
procedure set_worm(bl%,xy%,v%)
  bl% = bl% -1
  worm%[(bl%*2)+xy%] = v%
endproc
!***************************!
procedure get_wall(walln%,xy%)
  walln% = walln% - 1
  return(wall%[(walln%*4)+xy%])
endproc
!***************************!
procedure set_wall(walln%,xy%,v%)
  walln% = walln% - 1
  wall%[(walln%*4)+xy%] = v%
endproc
!***************************!
procedure check_collision
  if (hx%<1) or (hy% <1) or (hy%>92) or (hx%>237) then
    go% = 0
  endif
  loop for a% = 1 to wl% 
    if (hx% = get_worm(a%,1)) and (hy% = get_worm(a%,2)) and (a% <> hap%) then
      go% = 0
    endif
  endloop
  loop for a% = 1 to 4
    if (hx% >= wall%[((a%-1)*4)+1]/2) and  (hy%>= wall%[((a%-1)*4)+2]/2) and (hx% <= (wall%[((a%-1)*4)+3]/2)-1) and (hy% <= (wall%[((a%-1)*4)+4]/2)-1) then
      go% = 0
    endif
  endloop
  if (hx% = fx%) and (hy% = fy%) then
    if wl% < 50 then
      wl% = wl%+10
      if worm%[9] > worm%[10] then
        ma# = worm%[5]
        mi# = worm%[20]
      else
        ma# = worm%[20]
        mi# = worm%[5]
      endif
      sv# = mi# / ma#
      call disp_food
    else
      if level% <> 5 then
        level%=level% +1
        call new_level(level%)
      else
        go%=2
      endif
  endif
endif
  if (go% = 2) or (go%=0) then
    call curpos(20,10)
    print "http://www.geocities.com/SiliconValley/Way/8527"
    call curpos(25,6)
    call draw_logo(300,35)
  endif
   if go% = 0 then
    print "Game Over"
  endif
  if go% = 2 then
    print"You won the game"
  endif
  endproc
!***************************!
procedure rand(lbound%,ubound%)
  lbound# = lbound%
  ubound# = ubound%
  rn# = (sv# * (ubound# - lbound#))+ lbound#
  rs# = rn#
  if rs# = 0 then rs# = 1 endif
  sv# = rs#/(ubound#)
  rn% = rn#
  return(rn%)
endproc
!***************************!
procedure disp_food
ga2%=0
loop
  ga%=1
  fx% = rand(2,236)
  fy% = rand(2,91)
  loop for a% = 1 to 4
    if (fx% >= wall%[((a%-1)*4)+1]/2) and  (fy%>= wall%[((a%-1)*4)+2]/2) and (fx% <= (wall%[((a%-1)*4)+3]/2)-1) and (fy% <= wall%[((a%-1)*4)+1]/2) then
      ga%=0
    endif
  endloop
  loop for a% = 1 to wl%
  if (get_worm(a%,1) = fx%) and (get_worm(a%,2) = fy%) then
    ga%=0
  endif
  if ga% = 1 then 
    while ga2%=0
  endif
endloop
call draw_block(fx%,fy%)
endproc
!*************************!
Procedure draw_logo(logox%,logoy%)
  call color(3)
  call line( 8+logox%, 76+logoy%, 8+logox%, 77+logoy%)
  call line( 9+logox%, 75+logoy%, 9+logox%, 77+logoy%)
  call line( 10+logox%, 73+logoy%, 10+logox%, 77+logoy%)
  call line( 11+logox%, 72+logoy%, 11+logox%, 77+logoy%)
  call line( 12+logox%, 71+logoy%, 12+logox%, 77+logoy%)
  call line( 13+logox%, 70+logoy%, 13+logox%, 77+logoy%)
  call line( 14+logox%, 70+logoy%, 14+logox%, 77+logoy%)
  call line( 15+logox%, 70+logoy%, 15+logox%, 72+logoy%)
  call line( 15+logox%, 74+logoy%, 15+logox%, 75+logoy%)
  call line( 15+logox%, 76+logoy%, 15+logox%, 77+logoy%)
  call line( 16+logox%, 65+logoy%, 16+logox%, 67+logoy%)
  call line( 16+logox%, 70+logoy%, 16+logox%, 71+logoy%)
  call line( 16+logox%, 74+logoy%, 16+logox%, 75+logoy%)
  call line( 17+logox%, 64+logoy%, 17+logox%, 67+logoy%)
  call line( 17+logox%, 70+logoy%, 17+logox%, 71+logoy%)
  call line( 17+logox%, 72+logoy%, 17+logox%, 73+logoy%)
  call line( 17+logox%, 75+logoy%, 17+logox%, 76+logoy%)
  call line( 18+logox%, 63+logoy%, 18+logox%, 67+logoy%)
  call line( 18+logox%, 70+logoy%, 18+logox%, 71+logoy%)
  call line( 18+logox%, 72+logoy%, 18+logox%, 73+logoy%)
  call line( 18+logox%, 75+logoy%, 18+logox%, 76+logoy%)
  call line( 19+logox%, 62+logoy%, 19+logox%, 67+logoy%)
  call line( 19+logox%, 70+logoy%, 19+logox%, 71+logoy%)
  call line( 19+logox%, 73+logoy%, 19+logox%, 74+logoy%)
  call line( 20+logox%, 60+logoy%, 20+logox%, 67+logoy%)
  call line( 20+logox%, 70+logoy%, 20+logox%, 72+logoy%)
  call line( 20+logox%, 73+logoy%, 20+logox%, 74+logoy%)
  call line( 20+logox%, 76+logoy%, 20+logox%, 77+logoy%)
  call line( 21+logox%, 59+logoy%, 21+logox%, 67+logoy%)
  call line( 21+logox%, 70+logoy%, 21+logox%, 77+logoy%)
  call line( 22+logox%, 58+logoy%, 22+logox%, 67+logoy%)
  call line( 22+logox%, 70+logoy%, 22+logox%, 77+logoy%)
  call line( 23+logox%, 57+logoy%, 23+logox%, 67+logoy%)
  call line( 23+logox%, 70+logoy%, 23+logox%, 77+logoy%)
  call line( 24+logox%, 55+logoy%, 24+logox%, 67+logoy%)
  call line( 24+logox%, 70+logoy%, 24+logox%, 72+logoy%)
  call line( 24+logox%, 76+logoy%, 24+logox%, 77+logoy%)
  call line( 25+logox%, 54+logoy%, 25+logox%, 67+logoy%)
  call line( 25+logox%, 70+logoy%, 25+logox%, 71+logoy%)
  call line( 26+logox%, 53+logoy%, 26+logox%, 67+logoy%)
  call line( 26+logox%, 70+logoy%, 26+logox%, 71+logoy%)
  call line( 26+logox%, 72+logoy%, 26+logox%, 76+logoy%)
  call line( 27+logox%, 51+logoy%, 27+logox%, 67+logoy%)
  call line( 27+logox%, 70+logoy%, 27+logox%, 71+logoy%)
  call line( 27+logox%, 72+logoy%, 27+logox%, 76+logoy%)
  call line( 28+logox%, 50+logoy%, 28+logox%, 67+logoy%)
  call line( 28+logox%, 70+logoy%, 28+logox%, 71+logoy%)
  call line( 29+logox%, 49+logoy%, 29+logox%, 67+logoy%)
  call line( 29+logox%, 70+logoy%, 29+logox%, 72+logoy%)
  call line( 29+logox%, 76+logoy%, 29+logox%, 77+logoy%)
  call line( 30+logox%, 48+logoy%, 30+logox%, 67+logoy%)
  call line( 30+logox%, 70+logoy%, 30+logox%, 77+logoy%)
  call line( 31+logox%, 46+logoy%, 31+logox%, 67+logoy%)
  call line( 31+logox%, 70+logoy%, 31+logox%, 77+logoy%)
  call line( 32+logox%, 45+logoy%, 32+logox%, 67+logoy%)
  call line( 32+logox%, 70+logoy%, 32+logox%, 77+logoy%)
  call line( 33+logox%, 44+logoy%, 33+logox%, 67+logoy%)
  call line( 33+logox%, 70+logoy%, 33+logox%, 72+logoy%)
  call line( 33+logox%, 73+logoy%, 33+logox%, 77+logoy%)
  call line( 34+logox%, 42+logoy%, 34+logox%, 67+logoy%)
  call line( 34+logox%, 70+logoy%, 34+logox%, 71+logoy%)
  call line( 35+logox%, 41+logoy%, 35+logox%, 67+logoy%)
  call line( 36+logox%, 40+logoy%, 36+logox%, 67+logoy%)
  call line( 36+logox%, 71+logoy%, 36+logox%, 72+logoy%)
  call line( 36+logox%, 73+logoy%, 36+logox%, 77+logoy%)
  call line( 37+logox%, 39+logoy%, 37+logox%, 67+logoy%)
  call line( 37+logox%, 71+logoy%, 37+logox%, 77+logoy%)
  call line( 38+logox%, 70+logoy%, 38+logox%, 77+logoy%)
  call line( 39+logox%, 70+logoy%, 39+logox%, 77+logoy%)
  call line( 40+logox%, 70+logoy%, 40+logox%, 72+logoy%)
  call line( 40+logox%, 73+logoy%, 40+logox%, 77+logoy%)
  call line( 41+logox%, 76+logoy%, 41+logox%, 77+logoy%)
  call line( 43+logox%, 30+logoy%, 43+logox%, 46+logoy%)
  call line( 43+logox%, 54+logoy%, 43+logox%, 67+logoy%)
  call line( 43+logox%, 70+logoy%, 43+logox%, 72+logoy%)
  call line( 43+logox%, 73+logoy%, 43+logox%, 76+logoy%)
  call line( 44+logox%, 29+logoy%, 44+logox%, 45+logoy%)
  call line( 44+logox%, 55+logoy%, 44+logox%, 67+logoy%)
  call line( 44+logox%, 70+logoy%, 44+logox%, 77+logoy%)
  call line( 45+logox%, 27+logoy%, 45+logox%, 44+logoy%)
  call line( 45+logox%, 56+logoy%, 45+logox%, 67+logoy%)
  call line( 45+logox%, 70+logoy%, 45+logox%, 77+logoy%)
  call line( 46+logox%, 26+logoy%, 46+logox%, 43+logoy%)
  call line( 46+logox%, 49+logoy%, 46+logox%, 51+logoy%)
  call line( 46+logox%, 57+logoy%, 46+logox%, 67+logoy%)
  call line( 46+logox%, 70+logoy%, 46+logox%, 77+logoy%)
  call line( 47+logox%, 25+logoy%, 47+logox%, 42+logoy%)
  call line( 47+logox%, 48+logoy%, 47+logox%, 52+logoy%)
  call line( 47+logox%, 58+logoy%, 47+logox%, 67+logoy%)
  call line( 47+logox%, 70+logoy%, 47+logox%, 77+logoy%)
  call line( 48+logox%, 24+logoy%, 48+logox%, 41+logoy%)
  call line( 48+logox%, 47+logoy%, 48+logox%, 53+logoy%)
  call line( 48+logox%, 59+logoy%, 48+logox%, 67+logoy%)
  call line( 48+logox%, 70+logoy%, 48+logox%, 71+logoy%)
  call line( 48+logox%, 74+logoy%, 48+logox%, 77+logoy%)
  call line( 49+logox%, 25+logoy%, 49+logox%, 40+logoy%)
  call line( 49+logox%, 46+logoy%, 49+logox%, 54+logoy%)
  call line( 49+logox%, 60+logoy%, 49+logox%, 67+logoy%)
  call line( 49+logox%, 70+logoy%, 49+logox%, 71+logoy%)
  call line( 50+logox%, 27+logoy%, 50+logox%, 39+logoy%)
  call line( 50+logox%, 45+logoy%, 50+logox%, 55+logoy%)
  call line( 50+logox%, 61+logoy%, 50+logox%, 67+logoy%)
  call line( 50+logox%, 70+logoy%, 50+logox%, 74+logoy%)
  call line( 51+logox%, 28+logoy%, 51+logox%, 38+logoy%)
  call line( 51+logox%, 44+logoy%, 51+logox%, 56+logoy%)
  call line( 51+logox%, 62+logoy%, 51+logox%, 67+logoy%)
  call line( 51+logox%, 70+logoy%, 51+logox%, 72+logoy%)
  call line( 51+logox%, 76+logoy%, 51+logox%, 77+logoy%)
  call line( 52+logox%, 30+logoy%, 52+logox%, 37+logoy%)
  call line( 52+logox%, 43+logoy%, 52+logox%, 57+logoy%)
  call line( 52+logox%, 63+logoy%, 52+logox%, 67+logoy%)
  call line( 52+logox%, 70+logoy%, 52+logox%, 71+logoy%)
  call line( 52+logox%, 74+logoy%, 52+logox%, 77+logoy%)
  call line( 53+logox%, 31+logoy%, 53+logox%, 36+logoy%)
  call line( 53+logox%, 42+logoy%, 53+logox%, 58+logoy%)
  call line( 53+logox%, 64+logoy%, 53+logox%, 67+logoy%)
  call line( 53+logox%, 70+logoy%, 53+logox%, 72+logoy%)
  call line( 53+logox%, 76+logoy%, 53+logox%, 77+logoy%)
  call line( 54+logox%, 33+logoy%, 54+logox%, 35+logoy%)
  call line( 54+logox%, 41+logoy%, 54+logox%, 59+logoy%)
  call line( 54+logox%, 65+logoy%, 54+logox%, 67+logoy%)
  call line( 54+logox%, 70+logoy%, 54+logox%, 74+logoy%)
  call line( 55+logox%, 40+logoy%, 55+logox%, 60+logoy%)
  call line( 55+logox%, 66+logoy%, 55+logox%, 67+logoy%)
  call line( 55+logox%, 70+logoy%, 55+logox%, 71+logoy%)
  call line( 56+logox%, 39+logoy%, 56+logox%, 61+logoy%)
  call line( 56+logox%, 70+logoy%, 56+logox%, 71+logoy%)
  call line( 56+logox%, 74+logoy%, 56+logox%, 77+logoy%)
  call line( 57+logox%, 38+logoy%, 57+logox%, 62+logoy%)
  call line( 57+logox%, 70+logoy%, 57+logox%, 77+logoy%)
  call line( 58+logox%, 38+logoy%, 58+logox%, 63+logoy%)
  call line( 58+logox%, 70+logoy%, 58+logox%, 77+logoy%)
  call line( 59+logox%, 40+logoy%, 59+logox%, 64+logoy%)
  call line( 59+logox%, 70+logoy%, 59+logox%, 77+logoy%)
  call line( 60+logox%, 42+logoy%, 60+logox%, 65+logoy%)
  call line( 60+logox%, 70+logoy%, 60+logox%, 72+logoy%)
  call line( 60+logox%, 73+logoy%, 60+logox%, 74+logoy%)
  call line( 60+logox%, 76+logoy%, 60+logox%, 77+logoy%)
  call line( 61+logox%, 43+logoy%, 61+logox%, 66+logoy%)
  call line( 61+logox%, 70+logoy%, 61+logox%, 71+logoy%)
  call line( 61+logox%, 72+logoy%, 61+logox%, 73+logoy%)
  call line( 62+logox%, 44+logoy%, 62+logox%, 67+logoy%)
  call line( 62+logox%, 70+logoy%, 62+logox%, 71+logoy%)
  call line( 62+logox%, 72+logoy%, 62+logox%, 73+logoy%)
  call line( 62+logox%, 74+logoy%, 62+logox%, 76+logoy%)
  call line( 63+logox%, 46+logoy%, 63+logox%, 67+logoy%)
  call line( 63+logox%, 70+logoy%, 63+logox%, 71+logoy%)
  call line( 64+logox%, 47+logoy%, 64+logox%, 67+logoy%)
  call line( 64+logox%, 70+logoy%, 64+logox%, 72+logoy%)
  call line( 65+logox%, 48+logoy%, 65+logox%, 67+logoy%)
  call line( 65+logox%, 70+logoy%, 65+logox%, 77+logoy%)
  call line( 66+logox%, 49+logoy%, 66+logox%, 67+logoy%)
  call line( 66+logox%, 70+logoy%, 66+logox%, 77+logoy%)
  call line( 67+logox%, 51+logoy%, 67+logox%, 67+logoy%)
  call line( 67+logox%, 70+logoy%, 67+logox%, 77+logoy%)
  call line( 68+logox%, 52+logoy%, 68+logox%, 67+logoy%)
  call line( 68+logox%, 70+logoy%, 68+logox%, 77+logoy%)
  call line( 69+logox%, 53+logoy%, 69+logox%, 67+logoy%)
  call line( 69+logox%, 70+logoy%, 69+logox%, 71+logoy%)
  call line( 70+logox%, 55+logoy%, 70+logox%, 67+logoy%)
  call line( 70+logox%, 70+logoy%, 70+logox%, 71+logoy%)
  call line( 71+logox%, 56+logoy%, 71+logox%, 67+logoy%)
  call line( 71+logox%, 70+logoy%, 71+logox%, 71+logoy%)
  call line( 71+logox%, 72+logoy%, 71+logox%, 77+logoy%)
  call line( 72+logox%, 57+logoy%, 72+logox%, 67+logoy%)
  call line( 72+logox%, 70+logoy%, 72+logox%, 71+logoy%)
  call line( 72+logox%, 72+logoy%, 72+logox%, 77+logoy%)
  call line( 73+logox%, 59+logoy%, 73+logox%, 67+logoy%)
  call line( 73+logox%, 70+logoy%, 73+logox%, 77+logoy%)
  call line( 74+logox%, 60+logoy%, 74+logox%, 67+logoy%)
  call line( 74+logox%, 70+logoy%, 74+logox%, 77+logoy%)
  call line( 75+logox%, 61+logoy%, 75+logox%, 67+logoy%)
  call line( 75+logox%, 70+logoy%, 75+logox%, 77+logoy%)
  call line( 76+logox%, 63+logoy%, 76+logox%, 67+logoy%)
  call line( 76+logox%, 70+logoy%, 76+logox%, 72+logoy%)
  call line( 76+logox%, 76+logoy%, 76+logox%, 77+logoy%)
  call line( 77+logox%, 64+logoy%, 77+logox%, 67+logoy%)
  call line( 77+logox%, 70+logoy%, 77+logox%, 71+logoy%)
  call line( 78+logox%, 65+logoy%, 78+logox%, 67+logoy%)
  call line( 78+logox%, 70+logoy%, 78+logox%, 71+logoy%)
  call line( 78+logox%, 72+logoy%, 78+logox%, 73+logoy%)
  call line( 78+logox%, 74+logoy%, 78+logox%, 76+logoy%)
  call line( 79+logox%, 70+logoy%, 79+logox%, 71+logoy%)
  call line( 79+logox%, 72+logoy%, 79+logox%, 73+logoy%)
  call line( 79+logox%, 74+logoy%, 79+logox%, 76+logoy%)
  call line( 80+logox%, 70+logoy%, 80+logox%, 71+logoy%)
  call line( 80+logox%, 74+logoy%, 80+logox%, 75+logoy%)
  call line( 81+logox%, 70+logoy%, 81+logox%, 72+logoy%)
  call line( 81+logox%, 74+logoy%, 81+logox%, 75+logoy%)
  call line( 81+logox%, 76+logoy%, 81+logox%, 77+logoy%)
  call line( 82+logox%, 71+logoy%, 82+logox%, 77+logoy%)
  call line( 83+logox%, 72+logoy%, 83+logox%, 77+logoy%)
  call line( 84+logox%, 73+logoy%, 84+logox%, 77+logoy%)
  call line( 85+logox%, 75+logoy%, 85+logox%, 77+logoy%)
  call line( 86+logox%, 76+logoy%, 86+logox%, 77+logoy%)
endproc
!*************************!