From 256625afd77769b3c60acf1c53606fd654f5522c Mon Sep 17 00:00:00 2001
From: Yi-Jen Chen <89930807+yi-jenc@users.noreply.github.com>
Date: Fri, 22 Mar 2024 21:06:55 +0100
Subject: [PATCH] fix recursive solution for binary search in python (#279)

---
 .../python/05_binary_search_recursive.py        | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/03_recursion/python/05_binary_search_recursive.py b/03_recursion/python/05_binary_search_recursive.py
index 3ed0b23..c6461d6 100644
--- a/03_recursion/python/05_binary_search_recursive.py
+++ b/03_recursion/python/05_binary_search_recursive.py
@@ -1,17 +1,20 @@
 def binary_search(arr, target):
-    if not arr:
-        return -1
+    if len(arr) == 0:
+        return None
 
-    low = 0
-    high = len(arr) - 1
-    mid = (low + high) // 2
+    mid = len(arr) // 2
 
     if arr[mid] == target:
-        return target
+        return mid
     elif arr[mid] > target:
         return binary_search(arr[:mid], target)
     else:
-        return binary_search(arr[mid+1:], target)
+        recursive_response = binary_search(arr[(mid + 1) :], target)
+        return (
+            (mid + 1) + recursive_response
+            if recursive_response is not None
+            else recursive_response
+        )
 
 
 print(binary_search([6, 7, 8, 9, 10], 8))