Update permutations-ii.py

Author: kamyu104

Python/permutations-ii.py

@@ -25,12 +25,13 @@ def permuteUniqueRecu(self, result, used, cur, nums):
             result.append(cur + [])
             return
         for i in xrange(len(nums)):
-            if not used[i] and not (i > 0 and nums[i-1] == nums[i] and used[i-1]):
-                used[i] = True
-                cur.append(nums[i])
-                self.permuteUniqueRecu(result, used, cur, nums)
-                cur.pop()
-                used[i] = False
+            if used[i] or (i > 0 and nums[i-1] == nums[i] and not used[i-1]):
+                continue
+            used[i] = True
+            cur.append(nums[i])
+            self.permuteUniqueRecu(result, used, cur, nums)
+            cur.pop()
+            used[i] = False
 
 class Solution2:
     # @param num, a list of integer