Taking out copy.deepcopy() calls to drastically speed up the simple s…

…ub hacker.

simpleSubHacker.py

@@ -45,12 +45,12 @@ def addLettersToMapping(letterMapping, cipherword, candidate):
     # This function adds the letters of the candidate as potential
     # decryption letters for the cipherletters in the cipherletter
     # mapping.
+    # The letterMapping dictionary is modified in-place.
 
-    letterMapping = copy.deepcopy(letterMapping)
     for i in range(len(cipherword)):
         if candidate[i] not in letterMapping[cipherword[i]]:
             letterMapping[cipherword[i]].append(candidate[i])
-    return letterMapping
+
 
 
 def intersectMappings(mapA, mapB):
@@ -84,7 +84,7 @@ def removeSolvedLettersFromMapping(letterMapping):
     # to ['M']. Note that now that 'A' maps to only one letter, we can
     # remove 'M' from the list of letters for every other
     # letter. (This is why there is a loop that keeps reducing the map.)
-    letterMapping = copy.deepcopy(letterMapping)
+
     loopAgain = True
     while loopAgain:
         # First assume that we will not loop again:
@@ -107,7 +107,7 @@ def removeSolvedLettersFromMapping(letterMapping):
                     if len(letterMapping[cipherletter]) == 1:
                         # A new letter is now solved, so loop again.
                         loopAgain = True
-    return letterMapping
+    # Nothing is returned because letterMapping is modified in-place.
 
 
 def hackSimpleSub(message):
@@ -123,13 +123,13 @@ def hackSimpleSub(message):
 
         # Add the letters of each candidate to the mapping.
         for candidate in wordPatterns.allPatterns[wordPattern]:
-            newMap = addLettersToMapping(newMap, cipherword, candidate)
+            addLettersToMapping(newMap, cipherword, candidate)
 
         # Intersect the new mapping with the existing intersected mapping.
         intersectedMap = intersectMappings(intersectedMap, newMap)
-
     # Remove any solved letters from the other lists.
-    return removeSolvedLettersFromMapping(intersectedMap)
+    removeSolvedLettersFromMapping(intersectedMap)
+    return intersectedMap
 
 
 def decryptWithCipherletterMapping(ciphertext, letterMapping):