initial commit

algorithms/binary_search.py

@@ -0,0 +1,22 @@
+import pytest
+
+
+def binary_search(nums: list[int], target: int):
+    low, high = 0, len(nums) - 1
+    while low <= high:
+        mid = low + (high - low) // 2
+        if nums[mid] == target:
+            return mid
+        elif nums[mid] < target:
+            low = mid + 1
+        else:
+            high = mid - 1
+    return -1
+
+
+@pytest.mark.parametrize(
+    "nums,target,expected",
+    [([*range(5)], 2, 2), ([*range(5)], 6, -1), ([*range(20, 50)], 21, 1)],
+)
+def test_binary_search(nums: list[int], target: int, expected: int):
+    assert binary_search(nums, target) == expected