有没有更好的方法来检查这两个变量而不是四个ifs？
必须有两个变量，例如 A 和 B，这两个将取值 0 0、0 1、1 0 或 1 1。我需要检查这两个变量并返回 0 到 3 之间的值，有没有更好的比做四个if语句更像这样的方法：
if(B == 0 && A == 0){
return 0;
}
if(B == 0 && A == 1){
return 1;
}
if(B == 1 && A == 0){
return 2;
}
if(B ==1 && A == 1){
return 3;
}
回答
您显示的四个条件可以用单行解决：
return A + B * 2;
也就是说，当然，如果AandB值永远不会是0or以外的任何值1。
- For identical behavior to the original code, you could use `if ((A|B|1) == 1) return A + B * 2;` -- only return if both A and B are 0 or 1; fall through if either has any other value.
- Simple math > tons of `if` statements.
- This has two operators so it's basically multivariable calculus, but I'll allow it!
- personally, I prefer the `(B << 1) | A` route, since we're basically just mashing binary values together here.
- @ChristianGibbons Yeah - I considered a *similar* bitwise/logical solution but decided that old-fashioned maths was probably simpler in terms of understanding.