BinarySearch.py finally approved

Author: armanjscript

DataStructures/Section9/BinarySearch.py

@@ -0,0 +1,76 @@
+def binary_search_iterative(ordered_list, term):
+    size_of_list = len(ordered_list) - 1
+    index_of_first_element = 0
+    index_of_last_element = size_of_list
+
+    while index_of_first_element <= index_of_last_element:
+        mid_point = (index_of_first_element + index_of_last_element)//2
+
+        if ordered_list[mid_point] == term:
+            return mid_point
+        if ordered_list[mid_point] > term:
+            index_of_last_element = mid_point - 1
+        else:
+            index_of_first_element = mid_point + 1
+    if index_of_first_element > index_of_last_element:
+        return None
+
+
+print("---First Output---\n")
+list1 = [10, 30, 100, 120, 500]
+ 
+search_term = 10
+index_position1 = binary_search_iterative(list1, search_term)
+if index_position1 is None:
+    print("The data item {} is not found".format(search_term))
+else:
+    print("The data item {} is found at position {}".format(search_term, index_position1))
+    
+print("---Second Output---\n")
+
+list2 = ['book','data','packt', 'structure']
+ 
+search_term2 = 'structure'
+index_position2 = binary_search_iterative(list2, search_term2)
+if index_position2 is None:
+    print("The data item {} is not found".format(search_term2))
+else:
+    print("The data item {} is found at position {}".format(search_term2, index_position2))
+
+
+
+print('---Binary Search Recursive---\n')
+#Recursive Binary Search
+def binary_search_recursive(ordered_list, first_element_index, last_element_index, term):
+    if last_element_index < first_element_index:
+        return None 
+    else:
+        mid_point = (first_element_index + last_element_index) // 2
+        if ordered_list[mid_point] > term:
+            return binary_search_recursive(ordered_list, first_element_index, mid_point - 1, term)
+        elif ordered_list[mid_point] < term:
+            return binary_search_recursive(ordered_list, mid_point + 1, last_element_index, term)
+        else:
+            return mid_point
+
+print("Binary Search Recursive output1--\n")
+list1 = [10, 30, 100, 120, 500]
+ 
+search_term = 10
+index_position1 =  binary_search_recursive(list1, 0, len(list1)-1, search_term)
+if index_position1 is None:
+    print("The data item {} is not found".format(search_term))
+else:
+    print("The data item {} is found at position {}".format(search_term, index_position1))
+
+print('\n')
+
+print("Binary Search Recursive output2--\n")
+list2 = ['book','data','packt',  'structure']
+ 
+search_term2 = 'data'
+index_position2 = binary_search_recursive(list2, 0, len(list1)-1, search_term2)
+if index_position2 is None:
+    print("The data item {} is not found".format(search_term2))
+else:
+    print("The data item {} is found at position {}".format(search_term2, index_position2))