Modified Lab 1 IS

IS/Lab/Lab1/q5_john.py

@@ -0,0 +1,21 @@
+def main():
+    shift = (ord('C') - ord('y')) % 26
+
+    ctext = "XVIEWYWI"
+    plaintext = ""
+
+    for char in ctext:
+        if char.isalpha():
+            shifted = ord(char.lower()) - shift
+            if shifted < ord('a'):
+                shifted += 26
+            plaintext += chr(shifted)
+        else:
+            plaintext += char
+
+    print(f"Attack type: Known plaintext attack")
+    print(f"Ciphertext: {ctext}")
+    print(f"Decrypted: {plaintext}")
+
+if __name__ == '__main__':
+    main()