New Caesar

new_ceasar/sol.py

@@ -0,0 +1,30 @@
+#!/home/maxime/.pyvenv/bin/python3
+import string
+
+ALPHABET = string.ascii_lowercase[:16]
+
+def b16_decode(enc):
+    dec = ''
+    assert len(enc) % 2 == 0
+    for i in range(0, len(enc), 2):
+        char = 0
+        msb = ord(enc[i]) - ord('a')
+        lsb = ord(enc[i+1]) - ord('a')
+        char += (msb << 4) + lsb
+        dec += chr(char)
+    return dec
+
+def decode(c, k):
+    t1 = ord(c) - ord('a')
+    t2 = ord(k) - ord('a')
+    return ALPHABET[(t1 - t2) % len(ALPHABET)]
+
+with open("string", 'r') as f:
+    text = f.read().strip()
+    keyset = ALPHABET
+    for key in keyset:
+        decrypted = ''
+        for char in text:
+            decrypted += decode(char, key)
+        print(b16_decode(decrypted))
+