82 lines
2.2 KiB
Text
82 lines
2.2 KiB
Text
import "./str" for Str
|
|
|
|
var board = "ET AON RISBCDFGHJKLMPQ/UVWXYZ."
|
|
var digits = "0123456789"
|
|
var rows = " 26"
|
|
var escape = "62"
|
|
var key = "0452"
|
|
|
|
var encrypt = Fn.new { |message|
|
|
var msg = Str.upper(message).
|
|
where { |c| (board.contains(c) || digits.contains(c)) && !" /".contains(c) }.join()
|
|
var sb = ""
|
|
for (c in msg) {
|
|
var idx = board.indexOf(c)
|
|
if (idx > -1) {
|
|
var row = (idx/10).floor
|
|
var col = idx % 10
|
|
sb = sb + ((row == 0) ? "%(col)" : "%(rows[row])%(col)")
|
|
} else {
|
|
sb = sb + "%(escape)%(c)"
|
|
}
|
|
}
|
|
var enc = sb.bytes.toList
|
|
var i = 0
|
|
for (c in enc) {
|
|
var k = key[i%4].bytes[0] - 48
|
|
if (k != 0) {
|
|
var j = c - 48
|
|
enc[i] = 48 + ((j + k) % 10)
|
|
}
|
|
i = i + 1
|
|
}
|
|
return enc.map { |b| String.fromByte(b) }.join()
|
|
}
|
|
|
|
var decrypt = Fn.new { |encoded|
|
|
var enc = encoded.bytes.toList
|
|
var i = 0
|
|
for (c in enc) {
|
|
var k = key[i%4].bytes[0] - 48
|
|
if (k != 0) {
|
|
var j = c - 48
|
|
enc[i] = 48 + ((j >= k) ? (j - k) % 10 : (10 + j - k) % 10)
|
|
}
|
|
i = i + 1
|
|
}
|
|
var len = enc.count
|
|
var sb = ""
|
|
i = 0
|
|
while (i < len) {
|
|
var c = enc[i]
|
|
var idx = rows.indexOf((c-48).toString)
|
|
if (idx == -1) {
|
|
var idx2 = c - 48
|
|
sb = sb + board[idx2]
|
|
i = i + 1
|
|
} else if ("%(c-48)%(enc[i + 1]-48)" == escape) {
|
|
sb = sb + (enc[i + 2] - 48).toString
|
|
i = i + 3
|
|
} else {
|
|
var idx2 = idx * 10 + enc[i + 1] - 48
|
|
sb = sb + board[idx2]
|
|
i = i + 2
|
|
}
|
|
}
|
|
return sb
|
|
}
|
|
|
|
var messages = [
|
|
"Attack at dawn",
|
|
"One night-it was on the twentieth of March, 1888-I was returning",
|
|
"In the winter 1965/we were hungry/just barely alive",
|
|
"you have put on 7.5 pounds since I saw you.",
|
|
"The checkerboard cake recipe specifies 3 large eggs and 2.25 cups of flour."
|
|
]
|
|
for (message in messages) {
|
|
var encrypted = encrypt.call(message)
|
|
var decrypted = decrypt.call(encrypted)
|
|
System.print("\nMessage : %(message)")
|
|
System.print("Encrypted : %(encrypted)")
|
|
System.print("Decrypted : %(decrypted)")
|
|
}
|