Merge d525043 into de286fd

README.md

@@ -222,6 +222,7 @@ If you want to uninstall algorithms, it is as simple as:
     - [randomized_set](algorithms/set/randomized_set.py)
     - [set_covering](algorithms/set/set_covering.py)
 - [sort](algorithms/sort)
+    - [bitonic_sort](algorithms/sort/bitonic_sort.py)
     - [bogo_sort](algorithms/sort/bogo_sort.py)
     - [bubble_sort](algorithms/sort/bubble_sort.py)
     - [bucket_sort](algorithms/sort/bucket_sort.py)

README_CN.md

@@ -206,6 +206,7 @@ pip3 uninstall -y algorithms
     - [randomized_set：随机集合](algorithms/set/randomized_set.py)
     - [set_covering：集合覆盖](algorithms/set/set_covering.py)
 - [sort：排序](algorithms/sort)
+    - [bitonic_sort](algorithms/sort/bitonic_sort.py)
     - [bogo_sort](algorithms/sort/bogo_sort.py)
     - [bubble_sort：冒泡排序](algorithms/sort/bubble_sort.py)
     - [bucket_sort](algorithms/sort/bucket_sort.py)

README_GE.md

@@ -227,6 +227,7 @@ Um das Projekt zu deinstallieren tippen Sie folgendes:
     - [randomized_set](algorithms/set/randomized_set.py)
     - [set_covering](algorithms/set/set_covering.py)
 - [sort](algorithms/sort)
+    - [bitonic_sort](algorithms/sort/bitonic_sort.py)
     - [bogo_sort](algorithms/sort/bogo_sort.py)
     - [bubble_sort](algorithms/sort/bubble_sort.py)
     - [bucket_sort](algorithms/sort/bucket_sort.py)

README_JP.md

@@ -221,6 +221,7 @@ if __name__ == "__main__":
     - [randomized_set](algorithms/set/randomized_set.py)
     - [set_covering](algorithms/set/set_covering.py)
 - [sort : ソート](algorithms/sort)
+    - [bitonic_sort](algorithms/sort/bitonic_sort.py)
     - [bogo_sort](algorithms/sort/bogo_sort.py)
     - [bubble_sort](algorithms/sort/bubble_sort.py)
     - [bucket_sort](algorithms/sort/bucket_sort.py)

README_KR.md

@@ -218,6 +218,7 @@ if __name__ == "__main__":
     - [randomized_set](algorithms/set/randomized_set.py)
     - [set_covering](algorithms/set/set_covering.py)
 - [sort : 정렬 알고리즘](algorithms/sort)
+    - [bitonic_sort](algorithms/sort/bitonic_sort.py)
     - [bogo_sort](algorithms/sort/bogo_sort.py)
     - [bubble_sort](algorithms/sort/bubble_sort.py)
     - [cocktail_shaker_sort](algorithms/sort/cocktail_shaker_sort.py)

algorithms/sort/__init__.py

@@ -1,3 +1,4 @@
+from .bitonic_sort import *
 from .bogo_sort import *
 from .bubble_sort import *
 from .comb_sort import *

algorithms/sort/bitonic_sort.py

@@ -0,0 +1,43 @@
+def bitonic_sort(arr, reverse=False):
+    """
+    bitonic sort is sorting algorithm to use multiple process, but this code not containing parallel process
+    It can sort only array that sizes power of 2
+    It can sort array in both increasing order and decreasing order by giving argument true(increasing) and false(decreasing)
+    
+    Worst-case in parallel: O(log(n)^2)
+    Worst-case in non-parallel: O(nlog(n)^2)
+    
+    reference: https://en.wikipedia.org/wiki/Bitonic_sorter
+    """
+    def compare(arr, reverse):
+        n = len(arr)//2
+        for i in range(n):
+            if reverse != (arr[i] > arr[i+n]):
+                arr[i], arr[i+n] = arr[i+n], arr[i]
+        return arr
+
+    def bitonic_merge(arr, reverse):
+        n = len(arr)
+
+        if n <= 1:
+            return arr
+
+        arr = compare(arr, reverse)
+        left = bitonic_merge(arr[:n // 2], reverse)
+        right = bitonic_merge(arr[n // 2:], reverse)
+        return left + right
+
+    #end of function(compare and bitionic_merge) definition
+    n = len(arr)
+    if n <= 1:
+        return arr
+    # checks if n is power of two
+    if not (n and (not(n & (n - 1))) ):
+        raise ValueError("the size of input should be power of two")
+
+    left = bitonic_sort(arr[:n // 2], True)
+    right = bitonic_sort(arr[n // 2:], False)
+
+    arr = bitonic_merge(left + right, reverse)
+
+    return arr

tests/test_sort.py

@@ -1,4 +1,5 @@
 from algorithms.sort import (
+    bitonic_sort,
     bogo_sort,
     bubble_sort,
     comb_sort,
@@ -22,6 +23,14 @@ class TestSuite(unittest.TestCase):
     def test_bogo_sort(self):
         self.assertEqual([1, 5, 23],
                          bogo_sort([1, 23, 5]))
+
+    def test_bitonic_sort(self):
+        self.assertEqual([1, 2, 3, 5, 23, 57, 65, 1232],
+                         bitonic_sort([1, 3, 2, 5, 65, 23, 57, 1232]))
+        self.assertEqual([1, 2, 3, 5, 23, 57, 65, 1232],
+                         bitonic_sort([1, 3, 2, 5, 65, 23, 57, 1232],False))
+        self.assertEqual([1232, 65, 57, 23, 5, 3, 2, 1],
+                         bitonic_sort([1, 2, 3, 5, 65, 23, 57, 1232],True))  
 
     def test_bubble_sort(self):
         self.assertEqual([1, 5, 23, 57, 65, 1232],