diff --git a/challenge3.py b/challenge3.py
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+++ b/challenge3.py
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+# single-byte xor cipher
+from binascii import unhexlify
+hexed = "1b37373331363f78151b7f2b783431333d78397828372d363c78373e783a393b3736"
+unHexed = unhexlify(hexed)
+alphabet = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z']
+
+# generate a dict of possible answers and their decryption keys
+tableOfPossibleAnswers = {}
+for code in range(256):
+    possibleAnswer = ''.join(chr(byte ^ code) for byte in unHexed)
+    if possibleAnswer.isprintable():
+        tableOfPossibleAnswers[code] = possibleAnswer
+
+# weight the answers using a simple english alphabet list
+weightedCodes = {}
+for key,value in tableOfPossibleAnswers.items():
+    weightedCodes[value] = 0
+    for letter in alphabet:
+        if letter in value:
+            weightedCodes[value] += 1
+
+# find the highest value and return it and its corresponding key
+maxValue = max(weightedCodes.values())
+for key in weightedCodes:
+    if weightedCodes[key] == maxValue:
+        print(key, weightedCodes[key])
+    
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