77 lines
1.7 KiB
Python
77 lines
1.7 KiB
Python
import sys
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if len(sys.argv) < 2:
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print("Usage: python3 afreq.py [arquivo]")
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sys.exit(1)
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frequencias = {
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'A': 14.63,
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'B': 1.04,
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'C': 3.88,
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'D': 4.99,
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'E': 12.57,
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'F': 1.02,
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'G': 1.30,
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'H': 1.28,
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'I': 6.18,
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'J': 0.40,
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'K': 0.02,
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'L': 2.78,
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'M': 4.74,
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'N': 5.05,
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'O': 10.73,
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'P': 2.52,
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'Q': 1.20,
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'R': 6.53,
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'S': 7.81,
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'T': 4.34,
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'U': 4.63,
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'V': 1.67,
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'W': 0.01,
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'X': 0.21,
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'Y': 0.01,
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'Z': 0.47
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}
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frequencias = sorted(frequencias.keys(), key=lambda x: frequencias[x])
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frequencias.reverse()
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caracteres = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789'
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def afreq(string):
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# determina a frequencia de cada caractere na string
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# compara com a frequencia de cada caractere na lingua portuguesa
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# calcula a diferenca entre as frequencias
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str_freq = {}
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for c in string:
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if not c.isalnum():
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continue
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if c in str_freq:
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str_freq[c] += 1
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else:
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str_freq[c] = 1
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freq_sorted = sorted(str_freq.items(), key=lambda item: item[1])
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freq_sorted = [x[0] for x in freq_sorted]
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freq_sorted.reverse()
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possiveis_chaves = []
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for i, c in enumerate(frequencias):
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if c not in freq_sorted:
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continue
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index_c = caracteres.index(c)
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index_freq = caracteres.index(freq_sorted[i])
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# print(c, index_c, index_freq)
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possiveis_chaves.append((index_freq - index_c) % 26) # (indice da freq da letra na str - indice da letra em PT) % ignorar letras maiusculas
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return possiveis_chaves
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file_str = open(sys.argv[1], 'r').read()
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possiveis_chaves = afreq(file_str)
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print(possiveis_chaves) |