Zadanie3

@@ -0,0 +1,77 @@
+#XOR
+def xor(a, b):
+ 
+    # init
+    result = []
+ 
+    # porownuje znaki
+    for i in range(1, len(b)):
+        if a[i] == b[i]:
+            result.append('0')
+        else:
+            result.append('1')
+ 
+    return ''.join(result)
+ 
+ 
+# dzielenie modulo 2
+def divide(message, poly16):
+ 
+    # Ilosc bitow dla operacji XOR 'na raz'
+    step = len(poly16)
+ 
+    # podzial krok po kroku
+    temp = message[0 : step]
+ 
+    while step < len(message):
+ 
+        if temp[0] == '1':
+ 
+            temp = xor(poly16, temp) + message[step]
+ 
+        else:   
+            # jezeli 1 bit po lewej == 0
+            temp = xor('0'*step, temp) + message[step]
+ 
+        # kolejny krok
+        step += 1
+ 
+    if temp[0] == '1':
+        temp = xor(poly16, temp)
+    else:
+        temp = xor('0'*step, temp)
+ 
+    check = temp
+    return check
+
+ 
+def encode(message, poly16):
+ 
+    l_poly16 = len(poly16)
+ 
+    # Dodajemy n-1 "0" do wiadomosci
+    appended_message = message + '0'*(l_poly16-1)
+    remainder = divide(appended_message, poly16)
+ 
+    message_final = message + remainder
+    print("calosc : ",
+          message_final)
+
+
+
+def decode(message2, poly16):
+ 
+    l_poly16 = len(poly16)
+    appended_message2 = message2
+    remainder = divide(appended_message2, poly16)
+    print("reszta : ", remainder)
+
+
+    
+poly16 = "10001000000100001"
+print("podaj wiadomosc do zakodowania : ")
+message = str(raw_input())
+encode(message, poly16)
+print("podaj wiadomosc do odkodowania : ")
+message2 = str(raw_input())
+decode(message2, poly16)