Merge 1b4a15e into 8f68ac8

README_KR.md

@@ -1,4 +1,4 @@
-English(README_EN.md) | [简体中文](README_CN.md) | [Deutsch](README_GE.md) | 한국어 | [日本語](README_JP.md)
+[English](README.md) | [简体中文](README_CN.md) | [Deutsch](README_GE.md) | 한국어 | [日本語](README_JP.md)
 
 Python 버전 자료구조 및 알고리즘
 =========================================
@@ -11,7 +11,7 @@ Python 3로 구현한 간단하고 명확한 자료구조와 알고리즘들의
 
 ## 테스트 종류들
 
-### 단위별 테스트 사용
+### unittest 사용
 아래 명시된 모든 테스트 실행하기:
 
     $ python3 -m unittest discover tests
@@ -206,6 +206,7 @@ if __name__ == "__main__":
     - [search_range](algorithms/search/search_range.py)
     - [find_min_rotate](algorithms/search/find_min_rotate.py)
     - [search_rotate](algorithms/search/search_rotate.py)
+    - [jump_search](algorithms/search/jump_search.py)
 - [set : 집합](algorithms/set)
     - [randomized_set](algorithms/set/randomized_set.py)
     - [set_covering](algorithms/set/set_covering.py)

algorithms/search/__init__.py

@@ -6,3 +6,4 @@
 from .search_range import *
 from .find_min_rotate import *
 from .search_rotate import *
+from .jump_search import *

algorithms/search/jump_search.py

@@ -0,0 +1,40 @@
+import math
+
+def jump_search(arr,target):
+    """Jump Search
+        Worst-case Complexity: O(√n) (root(n))
+        All items in list must be sorted like binary search
+
+        Find block that contains target value and search it linearly in that block
+        It returns a first target value in array
+
+        reference: https://en.wikipedia.org/wiki/Jump_search
+
+    """
+    n = len(arr)
+    block_size = int(math.sqrt(n))
+    block_prev = 0
+    block= block_size
+
+    # return -1 means that array doesn't contain taget value
+    # find block that contains target value
+
+    if arr[n - 1] < target:
+        return -1  
+    while block <= n and arr[block - 1] < target:
+        block_prev = block
+        block += block_size
+
+    # find target value in block
+
+    while arr[block_prev] < target :
+        block_prev += 1
+        if block_prev == min(block, n) :
+            return -1
+
+    # if there is target value in array, return it
+
+    if arr[block_prev] == target :
+        return block_prev
+    else :
+        return -1

tests/test_search.py

@@ -6,7 +6,8 @@
     two_sum, two_sum1, two_sum2,
     search_range,
     find_min_rotate, find_min_rotate_recur,
-    search_rotate, search_rotate_recur
+    search_rotate, search_rotate_recur,
+    jump_search
 )
 
 import unittest
@@ -88,6 +89,13 @@ def test_search_rotate(self):
         self.assertEqual(8, search_rotate_recur(array, 0, 11, 5))
         self.assertEqual(-1, search_rotate_recur(array, 0, 11, 9))
 
+    def test_jump_search(self):
+        array = [1, 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 6]
+        self.assertEqual(10, jump_search(array, 5))
+        self.assertEqual(2, jump_search(array, 3))
+        self.assertEqual(-1, jump_search(array, 7))
+        self.assertEqual(-1, jump_search(array, -1))
+
 if __name__ == '__main__':
 
     unittest.main()