forked from kalmar/DALGLI0
78 lines
1.5 KiB
Plaintext
78 lines
1.5 KiB
Plaintext
#XOR
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def xor(a, b):
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# init
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result = []
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# porownuje znaki
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for i in range(1, len(b)):
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if a[i] == b[i]:
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result.append('0')
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else:
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result.append('1')
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return ''.join(result)
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# dzielenie modulo 2
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def divide(message, poly16):
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# Ilosc bitow dla operacji XOR 'na raz'
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step = len(poly16)
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# podzial krok po kroku
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temp = message[0 : step]
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while step < len(message):
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if temp[0] == '1':
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temp = xor(poly16, temp) + message[step]
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else:
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# jezeli 1 bit po lewej == 0
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temp = xor('0'*step, temp) + message[step]
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# kolejny krok
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step += 1
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if temp[0] == '1':
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temp = xor(poly16, temp)
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else:
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temp = xor('0'*step, temp)
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check = temp
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return check
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def encode(message, poly16):
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l_poly16 = len(poly16)
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# Dodajemy n-1 "0" do wiadomosci
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appended_message = message + '0'*(l_poly16-1)
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remainder = divide(appended_message, poly16)
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message_final = message + remainder
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print("calosc : ",
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message_final)
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def decode(message2, poly16):
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l_poly16 = len(poly16)
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appended_message2 = message2
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remainder = divide(appended_message2, poly16)
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print("reszta : ", remainder)
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poly16 = "10001000000100001"
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print("podaj wiadomosc do zakodowania : ")
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message = str(raw_input())
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encode(message, poly16)
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print("podaj wiadomosc do odkodowania : ")
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message2 = str(raw_input())
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decode(message2, poly16)
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