diff --git a/search.py b/search.py
index 1c03df0..4fcff8d 100644
--- a/search.py
+++ b/search.py
@@ -1,21 +1,32 @@
-"""
-Example 1:
-Input: nums = [-1, 0, 3, 5, 9, 12], target = 9
-Output: 4
-Explanation: 9 exists in nums and its index is 4
-
-Example 2:
-Input: nums = [-1, 0, 3, 5, 9, 12], target = 2
-Output: -1
-Explanation: 2 does not exist in nums so return -1
-
-Example 3:
-Input: nums = [-1, 0, 3, 5, 9, 12], target = 12
-Output: 5
-Explanation: 12 exists in the list and its index is 5
-
-Example 4:
-Input: nums = [-1, 0, 3, 5, 9, 12], target = -1
-Output: 0
-Explanation: -1 exists in the list and its index is 0
-"""
+
+def binary_search(nums, target):
+    left = 0
+    right = len(nums) -1
+
+    while left <= right:
+        mid = (left + right) // 2
+
+        if nums[mid] == target:
+            return mid
+        elif nums[mid] < target:
+            left = mid + 1
+        else:
+            right = mid - 1
+
+    return -1
+
+
+nums = [-1, 0, 3, 5, 9, 12]
+
+target = 9
+print(binary_search(nums, target))  # Output: 4
+
+target = 2
+print(binary_search(nums, target))  # Output: -1
+
+target = 12
+print(binary_search(nums, target))  # Output: 5
+
+target = -1
+print(binary_search(nums, target))  # Output: 0
+