From df7bde48f3f0bbf65830830d41e45903d13ef3ae Mon Sep 17 00:00:00 2001
From: julien lengrand-lambert <julien@lengrand.fr>
Date: Sun, 8 Dec 2013 20:26:27 +0100
Subject: [PATCH] Implements first version of duplicates removal. Prepares
 everything for another version that would not store any extra information

---
 04_linkedList/ll.py      | 31 +++++++++++++++++++++++++++++++
 04_linkedList/ll_test.py | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+)

diff --git a/04_linkedList/ll.py b/04_linkedList/ll.py
index bb0c799..722a01a 100644
--- a/04_linkedList/ll.py
+++ b/04_linkedList/ll.py
@@ -118,6 +118,37 @@ class SingleLinkedList():
 			item = item.nexti
 		return item.value
 
+	def remove_duplicates(self):
+		"""
+		Removes all duplicate values from the list
+		"""
+		# get an array of elements
+		# look at items
+		# if item value is in array, remove item
+		# otherwise, add value to array
+
+		values = []
+		item = self._root
+		ptr = 0
+		while(item is not None):
+			val = item.value
+			if val in values:
+				self.delete_item(ptr)
+				ptr -= 1
+			else:
+				values.append(val)
+
+			item = item.nexti
+			ptr += 1
+
+	def remove_duplicates_light(self):
+		"""
+		Removes all duplicate values from the list
+		NOTE: This version does not store any extra data, but will take some extra
+		time to complete
+		"""
+		pass
+
 	def __len__(self):
 		# Returns the number of elements in the list
 		return self._size
diff --git a/04_linkedList/ll_test.py b/04_linkedList/ll_test.py
index efae8a8..4eb4b0f 100644
--- a/04_linkedList/ll_test.py
+++ b/04_linkedList/ll_test.py
@@ -130,5 +130,41 @@ class test_single_linked_list(unittest.TestCase):
 
         self.assertRaises(Exception, lambda x: sl.get(14))
 
+    def test_remove_duplicates(self):
+
+        sl = SingleLinkedList()
+
+        sl.add(2)
+        sl.add(1)
+        sl.add(3)
+        sl.add(2)
+        sl.add(3)
+        sl.add(1)
+        sl.add(2)
+
+        self.assertEqual(7, len(sl))
+
+        sl.remove_duplicates()
+        self.assertEqual(3, len(sl))
+        self.assertEqual("2, 1, 3", sl.__str__())
+
+    def test_remove_duplicates_light(self):
+
+        sl = SingleLinkedList()
+
+        sl.add(2)
+        sl.add(1)
+        sl.add(3)
+        sl.add(2)
+        sl.add(3)
+        sl.add(1)
+        sl.add(2)
+
+        self.assertEqual(7, len(sl))
+
+        sl.remove_duplicates()
+        self.assertEqual(3, len(sl))
+        self.assertEqual("2, 1, 3", sl.__str__())
+
 if __name__ == "__main__":
     unittest.main()