27 lines
742 B
Text
27 lines
742 B
Text
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V symboltable = Array(‘a’..‘z’)
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F move2front_encode(strng)
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[Int] sequence
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V pad = copy(:symboltable)
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L(char) strng
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V indx = pad.index(char)
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sequence.append(indx)
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pad = [pad.pop(indx)] [+] pad
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R sequence
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F move2front_decode(sequence)
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[Char] chars
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V pad = copy(:symboltable)
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L(indx) sequence
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V char = pad[indx]
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chars.append(char)
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pad = [pad.pop(indx)] [+] pad
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R chars.join(‘’)
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L(s) [‘broood’, ‘bananaaa’, ‘hiphophiphop’]
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V encode = move2front_encode(s)
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print(‘#14 encodes to #.’.format(s, encode), end' ‘, ’)
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V decode = move2front_decode(encode)
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print(‘which decodes back to #.’.format(decode))
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assert(s == decode, ‘Whoops!’)
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