diff --git a/bitutilities.py b/bitutilities.py
index b976937..079e660 100644
--- a/bitutilities.py
+++ b/bitutilities.py
@@ -97,7 +97,8 @@ def binary_sum(first_term: BasicRegister, second_term: BasicRegister, return_rem
         return result
 
 
-def binary_subtraction_1_complement(first_term: BasicRegister, second_term: BasicRegister) -> BasicRegister:
+def binary_subtraction(first_term: BasicRegister, second_term: BasicRegister) -> BasicRegister:
+
     second_term.reverse()
 
     result: BasicRegister
@@ -105,7 +106,7 @@ def binary_subtraction_1_complement(first_term: BasicRegister, second_term: Basi
     result, final_carry = binary_sum(first_term, second_term, True)
 
     if final_carry:
-        return binary_sum(result, BasicRegister([True]))
+        return binary_sum(result, BasicRegister([True] * len(result)))
     else:
         result.reverse()
         return result
@@ -113,16 +114,12 @@ def binary_subtraction_1_complement(first_term: BasicRegister, second_term: Basi
 
 def align_registers(first_register: BasicRegister, second_register: BasicRegister) \
         -> tuple[BasicRegister, BasicRegister]:
-    size_a = len(first_register)
-    size_b = len(second_register)
+    first_size = len(first_register)
+    second_size = len(second_register)
 
-    required_size = max(size_a, size_b)
+    required_size = max(first_size, second_size)
 
-    a = first_register
-    b = second_register
-
-    if size_a != size_b:
-        a = a.adjusted_by_size(required_size)
-        b = b.adjusted_by_size(required_size)
-
-    return a, b
+    if first_size != second_size:
+        return first_register.adjusted_by_size(required_size), second_register.adjusted_by_size(required_size)
+    else:
+        return first_register, second_register