1 files changed, 6 insertions, 10 deletions
diff --git a/rfc1982_serial_number.py b/rfc1982_serial_number.py
index ae34167..e46974a 100755
--- a/rfc1982_serial_number.py
+++ b/rfc1982_serial_number.py
@@ -40,12 +40,9 @@ class Serial:
         return f"{int(self):{len(str(self.modulus))}d}"
 
 def find_intermediate(start, finish):
-    if start < finish:
-        return None
-    else:
-        wrap = start + ((Serial.modulus >> 1) - 2)
-        assert start < wrap and wrap < finish
-        return wrap
+    while not (start < finish): # sic: serial numbers are not (quite) integers
+        start += ((Serial.modulus >> 1) - 1)
+        yield start
 
 def main():
     from argparse import ArgumentParser
@@ -55,14 +52,13 @@ def main():
     ap.add_argument("finish", type = Serial)
     args = ap.parse_args()
 
-    wrap = find_intermediate(args.start, args.finish)
-
     print(f"Start at {args.start!s}")
 
-    if wrap is None:
+    if args.start < args.finish:
         print("No step needed")
     else:
-        print(f"Step via {wrap!s}")
+        for wrap in find_intermediate(args.start, args.finish):
+            print(f"Step via {wrap!s}")
 
     print(f"End at   {args.finish!s}")