47 lines
1.1 KiB
Python
47 lines
1.1 KiB
Python
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#!/usr/bin/env python3
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import numpy as np
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univers = ['a','b','c']
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message = "aabababac"
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def code_LZW(message, univers):
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msg = message
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dictionnaire = dict(zip(univers,[i for i in range (len(univers))]))
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w=""
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code =[]
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for c in msg:
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wc = w+c
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if wc in dictionnaire:
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w =wc
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else:
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code.append(dictionnaire[w])
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dictionnaire[wc] = len(dictionnaire)
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w = c
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if w:
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code.append(dictionnaire[w])
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return code,dictionnaire
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def decode_LZW(code,univers):
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dictionnaire = dict(zip([i for i in range(len(univers))],univers))
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w = dictionnaire[code.pop(0)]
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msg = [w]
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for k in code:
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if k in dictionnaire:
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entry = dictionnaire[k]
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elif k == len(dictionnaire):
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entry = w +w[0]
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msg.append(entry)
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dictionnaire[len(dictionnaire)] = w+entry[0]
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w = entry
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print(dictionnaire)
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return ''.join(msg)
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code,dictionnaire = code_LZW(message,univers)
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print(code)
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print(dictionnaire)
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msg = decode_LZW(code, univers)
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print(message)
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print(msg)
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