try rc4 encryption, this code uses 256 bits for the s array, that is 0 to 255

plaintext: Math 310 Proves!
the key for encryption: pwd12

plain text in ascii integer format = [77, 97, 116, 104, 32, 51, 49, 48, 32, 80, 114, 111, 118, 101, 115, 33]
key in ascii integer format = [112, 119, 100, 49, 50]

the cipher text is l¿oπ╦├<%ò├τï£ù╝
the corresponding integer format is [108, 168, 111, 227, 203, 195, 60, 22, 37, 149, 195, 231, 139, 156, 151, 188]
and the hex format is ['6c', 'a8', '6f', 'e3', 'cb', 'c3', '3c', '16', '25', '95', 'c3', 'e7', '8b', '9c', '97', 'bc']

...

1234

...

reference: https://sites.math.washington.edu/~nichifor/310_2008_Spring/Pres_RC4%20Encryption.pdf

https://en.wikipedia.org/wiki/RC4

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