Binary search done!

2 files changed, 59 insertions, 0 deletions

diff --git a/AlgoDesignAndTechniqueEdxPython/sources/binary_search.py b/AlgoDesignAndTechniqueEdxPython/sources/binary_search.py
new file mode 100644
index 0000000..5f51289
--- /dev/null
+++ b/AlgoDesignAndTechniqueEdxPython/sources/binary_search.py
@@ -0,0 +1,27 @@
+# Uses python3
+import sys
+
+def binarySearchRecursive(a, low, high, key):
+    if high < low:
+        return -1
+    mid = (int) (low + (high - low) / 2)
+    if key == a[mid]:
+        return mid
+    elif key < a[mid]:
+        return binarySearchRecursive(a, low, mid - 1, key) 
+    else:
+        return binarySearchRecursive(a, mid + 1, high, key)
+
+
+def binarySearch(a, key):
+    return binarySearchRecursive(a, 0, len(a) - 1, key)
+
+if __name__ == '__main__':
+    input = sys.stdin.read()
+    data = list(map(int, input.split()))
+    n = data[0]
+    m = data[n + 1]
+    a = data[1 : n + 1]
+    for x in data[n + 2:]:
+        # replace with the call to binary_search when implemented
+        print(binarySearch(a, x), end = ' ')
diff --git a/AlgoDesignAndTechniqueEdxPython/tests/binary_searchTest.py b/AlgoDesignAndTechniqueEdxPython/tests/binary_searchTest.py
new file mode 100644
index 0000000..2ff69bc
--- /dev/null
+++ b/AlgoDesignAndTechniqueEdxPython/tests/binary_searchTest.py
@@ -0,0 +1,32 @@
+'''
+Created on Oct 8, 2018
+
+@author: haidong
+'''
+import unittest
+
+from sources.binary_search import binarySearch
+
+class Test(unittest.TestCase):
+
+
+    def test1(self):
+        a = [1, 5, 8, 12, 13]
+        self.assertEqual(2, binarySearch(a, 8))
+
+    def test2(self):
+        a = [1, 5, 8, 12, 13]
+        self.assertEqual(0, binarySearch(a, 1))
+
+    def test3(self):
+        a = [1, 5, 8, 12, 13]
+        self.assertEqual(-1, binarySearch(a, 23))
+
+    def test4(self):
+        a = [1, 5, 8, 12, 13]
+        self.assertEqual(-1, binarySearch(a, 11))
+
+
+if __name__ == "__main__":
+    #import sys;sys.argv = ['', 'Test.testName']
+    unittest.main()
\ No newline at end of file