diff --git a/bitutilities.py b/bitutilities.py
index 052163e..c586d9d 100644
--- a/bitutilities.py
+++ b/bitutilities.py
@@ -82,12 +82,12 @@ def binary_sum(a_original: BasicRegister, b_original: BasicRegister) -> BasicReg
 
     required_size = max(size_a, size_b)
 
+    a = a_original
+    b = b_original
+
     if size_a != size_b:
-        a = a_original.adjusted_by_size(required_size)
-        b = b_original.adjusted_by_size(required_size)
-    else:
-        a = a_original
-        b = b_original
+        a = a.adjusted_by_size(required_size)
+        b = b.adjusted_by_size(required_size)
 
     c = BasicRegister([False] * required_size)