Data commit

Task/Vigen-re-cipher/F-Sharp/vigen-re-cipher.fs

@@ -0,0 +1,27 @@
+module vigenere =
+    let keyschedule (key:string) =
+        let s = key.ToUpper().ToCharArray() |> Array.filter System.Char.IsLetter
+        let l = Array.length s
+        (fun n -> int s.[n % l])
+
+    let enc k c = ((c + k - 130) % 26) + 65
+    let dec k c = ((c - k + 130) % 26) + 65
+    let crypt f key = Array.mapi (fun n c -> f (key n) c |> char)
+
+    let encrypt key (plaintext:string) =
+        plaintext.ToUpper().ToCharArray()
+        |> Array.filter System.Char.IsLetter
+        |> Array.map int
+        |> crypt enc (keyschedule key)
+        |> (fun a -> new string(a))
+
+    let decrypt key (ciphertext:string) =
+        ciphertext.ToUpper().ToCharArray()
+        |> Array.map int
+        |> crypt dec (keyschedule key)
+        |> (fun a -> new string(a))
+
+let passwd = "Vigenere Cipher"
+let cipher = vigenere.encrypt passwd "Beware the Jabberwock, my son! The jaws that bite, the claws that catch!"
+let plain = vigenere.decrypt passwd cipher
+printfn "%s\n%s" cipher plain