for (auto& sub_graph : model->subgraphs) {
    for (auto& op : sub_graph->operators) {
      if (tflite::GetBuiltinCode(
              model->operator_codes[op->opcode_index].get()) ==
          tflite::BuiltinOperator_FULLY_CONNECTED) {
        // inject min/max to the input and output tensors
        auto& input_tensor = sub_graph->tensors[op->inputs[0]];