changed count to return 0 for slices outside the source string
diff --git a/Objects/stringlib/count.h b/Objects/stringlib/count.h
index 84a852f..367a15c 100644
--- a/Objects/stringlib/count.h
+++ b/Objects/stringlib/count.h
@@ -15,7 +15,7 @@
 
     if (sub_len == 0) {
         if (str_len < 0)
-            return 1; /* start >= len(str) */
+            return 0; /* start > len(str) */
         return str_len + 1;
     }