F correct_case(string)
   R string.filter(s -> s.is_alpha()).map(s -> s.uppercase()).join(‘’)

F permu(String alp; num)
   R alp[num..]‘’alp[0 .< num]

F rotate_wheels(lalph, ralph, key)
   V newin = ralph.index(key)
   R (permu(lalph, newin), permu(ralph, newin))

F scramble_wheels(String =lalph, String =ralph)
   lalph = lalph[0]‘’lalph[2.<14]‘’lalph[1]‘’lalph[14..]
   ralph = ralph[1.<3]‘’ralph[4.<15]‘’ralph[3]‘’ralph[15..]‘’ralph[0]
   R (lalph, ralph)

F do_chao(=msg, =lalpha, =ralpha, en = 1B, show = 0B)
   msg = correct_case(msg)
   V out = ‘’
   I show
      print(‘=’ * 54)
      print((10 * ‘ ’)‘left:’(21 * ‘ ’)‘right: ’)
      print(‘=’ * 54)
      print(lalpha‘ ’ralpha" \n")
   L(l) msg
      I en
         (lalpha, ralpha) = rotate_wheels(lalpha, ralpha, l)
         out ‘’= lalpha[0]
      E
         (ralpha, lalpha) = rotate_wheels(ralpha, lalpha, l)
         out ‘’= ralpha[0]
      (lalpha, ralpha) = scramble_wheels(lalpha, ralpha)
      I show
         print(lalpha‘ ’ralpha)
   R out

V lalpha = ‘HXUCZVAMDSLKPEFJRIGTWOBNYQ’
V ralpha = ‘PTLNBQDEOYSFAVZKGJRIHWXUMC’
V msg = ‘WELLDONEISBETTERTHANWELLSAID’

print(‘L: ’lalpha)
print(‘R: ’ralpha)
print(‘I: ’msg)
V o = do_chao(msg, lalpha, ralpha, 1B, 0B)
print(‘O: ’o)
print(‘D: ’do_chao(o, lalpha, ralpha, 0B, 0B))
print()

do_chao(msg, lalpha, ralpha, 1B, 1B)