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14bcb580d5
* Initial fix for mypy errors in some cipher algorithms * fix(mypy): Update type hints * fix(mypy): Update type hints for enigma_machine2.py * Update as per the suggestion Co-authored-by: Christian Clauss <cclauss@me.com> Co-authored-by: Christian Clauss <cclauss@me.com>
83 lines
1.9 KiB
Python
83 lines
1.9 KiB
Python
"""
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Author: Mohit Radadiya
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"""
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from string import ascii_uppercase
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dict1 = {char: i for i, char in enumerate(ascii_uppercase)}
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dict2 = {i: char for i, char in enumerate(ascii_uppercase)}
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# This function generates the key in
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# a cyclic manner until it's length isn't
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# equal to the length of original text
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def generate_key(message: str, key: str) -> str:
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"""
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>>> generate_key("THE GERMAN ATTACK","SECRET")
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'SECRETSECRETSECRE'
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"""
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x = len(message)
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i = 0
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while True:
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if x == i:
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i = 0
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if len(key) == len(message):
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break
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key += key[i]
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i += 1
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return key
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# This function returns the encrypted text
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# generated with the help of the key
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def cipher_text(message: str, key_new: str) -> str:
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"""
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>>> cipher_text("THE GERMAN ATTACK","SECRETSECRETSECRE")
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'BDC PAYUWL JPAIYI'
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"""
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cipher_text = ""
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i = 0
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for letter in message:
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if letter == " ":
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cipher_text += " "
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else:
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x = (dict1[letter] - dict1[key_new[i]]) % 26
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i += 1
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cipher_text += dict2[x]
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return cipher_text
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# This function decrypts the encrypted text
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# and returns the original text
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def original_text(cipher_text: str, key_new: str) -> str:
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"""
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>>> original_text("BDC PAYUWL JPAIYI","SECRETSECRETSECRE")
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'THE GERMAN ATTACK'
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"""
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or_txt = ""
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i = 0
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for letter in cipher_text:
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if letter == " ":
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or_txt += " "
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else:
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x = (dict1[letter] + dict1[key_new[i]] + 26) % 26
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i += 1
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or_txt += dict2[x]
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return or_txt
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def main() -> None:
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message = "THE GERMAN ATTACK"
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key = "SECRET"
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key_new = generate_key(message, key)
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s = cipher_text(message, key_new)
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print(f"Encrypted Text = {s}")
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print(f"Original Text = {original_text(s, key_new)}")
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if __name__ == "__main__":
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import doctest
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doctest.testmod()
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main()
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