将字符指针和字符字节声明为无符号类型的，这样可以防止8位字符的符号扩展问题。

Declare character Pointers and character bytes as unsigned to avoid sign extension problems with 8-bit characters.

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无符号字符数据类型和二进制数据类型将产生错误的计算结果，会当成有符号的数据类型进行计算。

The unsigned char data type, and byte data type will yield incorrect results and act as though they are signed types i. e. type char.

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无符号字符数据类型和二进制数据类型将产生错误的计算结果，会当成有符号的数据类型进行计算。

The unsigned char data type, and byte data type will yield incorrect results and act as though they are signed types i. e. type char.

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