Update linear_search.py

searches/linear_search.py

@@ -11,7 +11,7 @@
 """
 
 
-def linear_search(sequence, target):
+def linear_search(sequence: list, target: int) -> int:
     """Pure implementation of linear search algorithm in Python
 
     :param sequence: a collection with comparable items (as sorted items not required
@@ -38,6 +38,41 @@ def linear_search(sequence, target):
     return None
 
 
+def rec_linear_search(sequence: list, low: int, high: int, target: int) -> int:
+    '''
+    Pure implementation of recursive linear search algorithm in Python
+
+    :param sequence: An array of items
+    :param low: Lower bound of the array
+    :param high: Higher bound of the array
+    :param target: The element to be found
+    :return: Index of the key or -1 if key not found or None in case of an exception
+
+    Examples:
+    >>> rec_linear_search([0, 30, 500, 100, 700], 0, 4, 0)
+    The element 0 is present at index 0
+
+    >>> rec_linear_search([0, 30, 500, 100, 700], 0, 4, 700)
+    The element 700 is present at index 4
+
+    >>> rec_linear_search([0, 30, 500, 100, 700], 0, 4, 30)
+    The element 5 is present at index 1
+
+    >>> rec_linear_search([0, 30, 500, 100, 700], 0, 4, -6)
+    The element -6 is not present in the array
+    '''
+    if high < low:
+        return -1
+    try:
+        if sequence[low] == target:
+            return low
+        if sequence[high] == target:
+            return high
+        return rec_linear_search(sequence, low + 1, high - 1, target)
+    except IndexError:
+        print('Invalid upper or lower bound!')
+
+
 if __name__ == "__main__":
     user_input = input("Enter numbers separated by comma:\n").strip()
     sequence = [int(item) for item in user_input.split(",")]