From e6305c4b0086161768c7f2d7e104107a82f04e4a Mon Sep 17 00:00:00 2001
From: Leon Vatthauer <leon.vatthauer@fau.de>
Date: Wed, 16 Oct 2024 11:09:46 +0200
Subject: [PATCH] add caesar and masc encryption

---
 caesar.py |  2 ++
 masc.py   | 23 +++++++++++++++++++++++
 2 files changed, 25 insertions(+)
 create mode 100644 caesar.py
 create mode 100644 masc.py

diff --git a/caesar.py b/caesar.py
new file mode 100644
index 0000000..efc1ac6
--- /dev/null
+++ b/caesar.py
@@ -0,0 +1,2 @@
+def caesar(k : int, plain : str) -> str:
+  return str([chr(ord(c) + k) for c in plain])
diff --git a/masc.py b/masc.py
new file mode 100644
index 0000000..bc99564
--- /dev/null
+++ b/masc.py
@@ -0,0 +1,23 @@
+default_alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+
+def masc(k : str, plain : str, alphabet : str = default_alphabet):
+  # make sure that k only contains characters from alphabet
+  for c in k:
+    if c not in alphabet:
+      raise ValueError("key contains character thats not in alphabet, namely: " + c)
+
+  # build key
+  ## make unique
+  k_unique = []
+  for c in k:
+    if not (c in k_unique):
+      k_unique.append(c)
+
+  ## append alphabet
+  last = k_unique[len(k_unique) - 1]
+  alphabet_pos = alphabet.index(last)
+  for i in list(range(alphabet_pos + 1, len(alphabet))) + list(range(0, alphabet_pos)):
+    if alphabet[i] not in k_unique:
+      k_unique.append(alphabet[i])
+
+  return k_unique