check sum code

例句：

1. 1.The system uses a checksum code to ensure data integrity.
   该系统使用校验和代码来确保数据完整性。
2. 2. The checksum code was used to verify the authenticity of the document.
   校验和代码被用来验证文件的真实性。
3. 3.The checksum code was sent as an attachment to the email.
   校验和代码作为附件发送到电子邮件中。