简写 C++ if else 语句
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shorthand c++ if else statement
提问by kevorski
So I'm just curious if there is a short hand statement to this:
所以我很好奇是否有一个简短的声明：
if(number < 0 )
bigInt.sign = 0;
else
bigInt.sign = 1;
I see all these short hand statements for if a < b and such.
我看到所有这些关于 if a < b 等的简短陈述。
I'm not sure on how to do it properly and would like some input on this.
我不确定如何正确地做到这一点，并希望对此提供一些意见。
Thanks!
谢谢！
I actually just figured it out right before you guys had answered.
我实际上只是在你们回答之前就想通了。
I'm using bigInt.sign = (number < 0) ? 1 : 0
我正在使用 bigInt.sign = (number < 0) ? 1 : 0
回答by Bla...
The basic syntax for using ternary operator is like this:
使用三元运算符的基本语法是这样的：
(condition) ? (if_true) : (if_false)
For you case it is like this:
对于你的情况，它是这样的：
number < 0 ? bigInt.sign = 0 : bigInt.sign = 1;
回答by Bla...
try this:
尝试这个：
bigInt.sign = number < 0 ? 0 : 1
回答by M.M
Yes:
是的：
bigInt.sign = !(number < 0);
The !operator always evaluates to trueor false. When converted to int, these become 1and 0respectively.
该!运营商始终计算为true或false。当转换为 时int，它们分别变为1和0。
Of course this is equivalent to:
当然，这相当于：
bigInt.sign = (number >= 0);
Here the parentheses are redundant but I add them for clarity. All of the comparison and relational operator evaluate to trueor false.
这里的括号是多余的，但为了清楚起见，我添加了它们。所有比较和关系运算符的计算结果都为true或false。
回答by Fantastic Mr Fox
Depending on how often you use this in your code you could consider the following:
根据您在代码中使用它的频率，您可以考虑以下几点：
macro
宏
#define SIGN(x) ( (x) >= 0 )
Inline function
内联函数
inline int sign(int x)
{
return x >= 0;
}
Then you would just go:
然后你就去：
bigInt.sign = sign(number);
