diff --git a/buggy.py b/buggy.py
--- a/buggy.py
+++ b/buggy.py
@@ -15,5 +15,5 @@
             if i % 2 == 0:
                 count += int(n[i])
             else:
-                count += int(n[i])
+                count -= int(n[i])
         return count
