rhs_batch_dim_size++;
    } else if (absl::StrContains(out_eq, c)) {
      int out_idx = out_eq.find(c);
      if (out_idx < rhs_out_idx_end) {
        return false;
      }
      if (out_idx < rhs_out_idx_start) rhs_out_idx_start = out_idx;
      if (out_idx > rhs_out_idx_end) rhs_out_idx_end = out_idx;
    }
  }

  if (lhs_batch_dim_size != rhs_batch_dim_size && lhs_batch_dim_size != 0 &&