这个语法在C中意味着什么？变量=（arg0 + arg1 == arg2？0x1：0x0）＆amp; 0xFF的;

Question

我通常在Java工作，我得到了一些C代码，我没有在任何文档中找到它 - 它可能没有帮助，我不知道它应该做什么所以我不喜欢＃39;知道要在文档中查找的位置！

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Answer 1

Both the mask with 0xff and the ternary operator are redundant.

The first operation arg0 + arg1 == arg2 is a simple comparison.

C does not have boolean types for the comparison operators, the result is of type int and its value is either 0 for false or 1 for true.

The ternary operator, almost the same as Java's, is redundant as it evaluates as 0x1 for non 0 and 0x0 for 0.

The bitwise mask operator & is also redundant because 0 & 0xff is 0 and 1 & 0xff is 1.

Overall, this expression simplifies to just variable = (arg0 + arg1 == arg2); which can be written more explicitly as

if (arg0 + arg1 == arg2)
    variable = 1;
else
    variable = 0;

Answer 2

arg0 + arg1 == arg2 ? 0x1 : 0x0表示0x1 arg0 + arg1 == arg2为true而0x0表示arg0 + arg1 == arg2为false。

其他所有内容都与Java相同。

？：是一个名为Ternary的快速if / then / else运算符，正如其他人所提到的那样。

Answer 3

1. arg0 + arg1与arg2进行比较，如果确实输出为0x1其他0X0。然后在结果和and之间进行按位0xff操作。

按位并且与0xff产生相同的值，即

a & 0xff = a;

三元条件

a ? b : c

如果a为真，则结果为b else c。