fix the merge sort

bixiang · Jun 11, 2015 · cc67864 · cc67864
1 parent b57285c
commit cc67864
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Showing 2 changed files with 7 additions and 4 deletions.
diff --git a/sort/merge_sort.py b/sort/merge_sort.py
@@ -16,5 +16,5 @@ def merge(left,right):
         return l
     else:
         middle=length/2
-        return merge(l[:middle],l[middle:])
+        return merge(merge_sort(l[:middle]),merge_sort(l[middle:]))
 
diff --git a/sort/test_sort.py b/sort/test_sort.py
@@ -16,13 +16,15 @@
 cases=[
     [],
     [1],
-    [1,3,1,4,21]
+    [1,3,1,4,21],
+    [3,1,2,4]
 ]
 
 answers=[
     [],
     [1],
-    [1,1,3,4,21]
+    [1,1,3,4,21],
+    [1,2,3,4]
 ]
 
 def test_sort(func):
@@ -31,7 +33,8 @@ def test_sort(func):
     just because the bucket sort,count sort,radix sort.
 
     '''
-    for index,case in enumerate(cases):
+    tmp_cases=[i[:] for i in cases]
+    for index,case in enumerate(tmp_cases):
         try:
             assert func(case)==answers[index]
         except Exception: