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31. ROT-18 Cipher (encoder / decoder) example ( Enter your problem )

1. Examples





1. ROT-18 Cipher encoder

Text : ABCD efghi 12345
ROT Method : ROT-18 (a-z, 0-9)


Solution:
The ROT-18 cipher is a shift cipher, where (ROT-13) each letter is shifted by 13 positions down the alphabet 'A-Z' and (ROT-5) each digit is shifted by 5 positions down in 0123456789

ROT-18 = ROT-13 + ROT-5
ROT-13
PlaintextABCDEFGHIJKLMNOPQRSTUVWXYZ
x012345678910111213141516171819202122232425
(x+13) mod 26131415161718192021222324250123456789101112
CiphertextNOPQRSTUVWXYZABCDEFGHIJKLM

ROT-5
Plaintext Alphabet0123456789
Ciphertext Alphabet5678901234

Plaintext : ABCD efghi 12345
Ciphertext : NOPQ rstuv 67890

2. ROT-18 Cipher encoder

Text : hello world 56789
ROT Method : ROT-18 (a-z, 0-9)


Solution:
The ROT-18 cipher is a shift cipher, where (ROT-13) each letter is shifted by 13 positions down the alphabet 'A-Z' and (ROT-5) each digit is shifted by 5 positions down in 0123456789

ROT-18 = ROT-13 + ROT-5
ROT-13
PlaintextABCDEFGHIJKLMNOPQRSTUVWXYZ
x012345678910111213141516171819202122232425
(x+13) mod 26131415161718192021222324250123456789101112
CiphertextNOPQRSTUVWXYZABCDEFGHIJKLM

ROT-5
Plaintext Alphabet0123456789
Ciphertext Alphabet5678901234

Plaintext : hello world 56789
Ciphertext : uryyb jbeyq 01234





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