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Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

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Curious Question About Unknown Data

From: andrew cooke <andrew@...>

Date: Sun, 1 Sep 2013 19:52:58 -0400

http://stackoverflow.com/questions/18560948/encrypted-string-by-unknown-method

if ctext is the given text, then my code so far (python 3) is:

  from base64 import b64decode

  ctext = b64decode(ctext)

  from binascii import hexlify

  print(hexlify(ctext))

  def bcd(bs):
      for b in bs:
	  yield b >> 4
	  yield b & 0x0f

  digits = list(bcd(ctext))
  print(max(digits))
  print(len(digits))

  from collections import Counter

  c = Counter(digits)
  print(c)

  print(digits)
  i = iter(digits)
  ns = list(map(lambda ab: ab[0]*10+ab[1], zip(i, i)))
  print (ns)

  # gave a jumble of punctuation and spaces
  #t = ''.join(map(chr, ns))
  #print(t)

  i = iter(ns)
  triplets = list(zip(i, i, i))

  print(sorted(Counter(a[0] for a in triplets).items()))
  print(sorted(Counter(a[1] for a in triplets).items()))
  print(sorted(Counter(a[2] for a in triplets).items()))

and the final prints are:

[(32, 1), (33, 308), (34, 540), (35, 452), (36, 774), (37, 316)]
[(30, 86), (31, 111), (32, 301), (33, 225), (34, 131), (35, 162), (36, 133),
(37, 286), (38, 161), (39, 283), (41, 185), (42, 46), (43, 129), (44, 70),
(45, 57), (46, 25)]
[(20, 2391)]

Andrew

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