beam: fix rotated_binary_search test pivot expectation (left-rotation semantics)

wizard-work/beam/test_rotated_binary_search.py

@@ -24,8 +24,9 @@ def test_rotated():
     base = [1,2,3,4,5,6,7]
     for r in range(len(base)):
         arr = base[r:] + base[:r]
-        assert find_pivot(arr) == r, (r, find_pivot(arr))
-        assert count_rotations(arr) == r
+        expected_pivot = (len(base) - r) % len(base)
+        assert find_pivot(arr) == expected_pivot, (r, find_pivot(arr), expected_pivot)
+        assert count_rotations(arr) == expected_pivot
         for t in base:
             i = search(arr, t)
             assert i != -1 and arr[i] == t