fix

src/with_indices.rs

@@ -60,7 +60,7 @@ where
       if char_index == end_char_index {
         end_byte_index = Some(byte_index + last_byte_index);
         *self.last_char_index_to_byte_index.borrow_mut() =
-          (end_char_index, byte_index);
+          (end_char_index, byte_index + last_byte_index);
         break;
       }
       char_index += 1;