大家好， 这一直是一个有趣的话题。你可以使用temp（作为第三个变量）交换两个 数字（比如a和b）。你也可以在不使用第三个变量的情况下交换 。[a = a + b; b = a-b; a = a-b; ]这也是在三个陈述中完成的。任何人都可以建议交换任何东西 少于那个。

hello all, this has been an interesting topic since long. you can swap two numbers (say a and b) using temp(as third variable). you can also swap without using third variable.like[ a=a+b;b=a-b;a=a-b; ]This was also done in three statements. Can anyon suggest this swapping in anything less then that.

a = a-（b =（a = a + b）-b）; - 如果每个人都读到USENET会更好： www.expita/nomime.html wwwmeister/news/learn2quote2.html www.catb/~esr/faqs/smart-questions.html

a = a-(b=(a=a+b)-b); -- USENET would be a better place if everybody read: www.expita/nomime.html wwwmeister/news/learn2quote2.html www.catb/~esr/faqs/smart-questions.html

[a = a + b; b = a-b; a = a-b;由于可能的溢出，交换两个数字的方法很糟糕。不使用临时变量的更好方法是使用 XOR技巧[*]（也适用于非整数类型）。但是，最好的方式可能只是使用标准的临时变量，让 编译器进行优化。 [*] a ^ = b; b ^ = A; a ^ = b;

[ a=a+b;b=a-b;a=a-b; ] is a bad way to swap two numbers due to possible overflow. A better method without using a temporary variable is to use the XOR trick[*] (which works for non-integral types as well). But, the best way is probably just to use a standard temporary variable and let the compiler do the optimization. [*] a^=b; b^=a; a^=b;

a = a-（b =（a = a + b）-b）;

a = a-(b=(a=a+b)-b);

这比原始的愚蠢更糟糕，因为它总是调用 未定义的行为。 Rob Gamble

This is even worse than the original silliness as it always invokes undefined behavior. Rob Gamble