玩玩小技巧(1)_三种方法不使用临时变量交换两个数的值

int a = 3, b = 4;
//function 1
a = a + b;
b = a - b;
a = a - b;
Console.WriteLine(a);//4
Console.WriteLine(b);//3
//function 2
a = a ^ b;
b = b ^ a;
a = a ^ b;
Console.WriteLine(a);//3
Console.WriteLine(b);//4
//function 3
b = a + (a = b) * 0;
Console.WriteLine(a);//4
Console.WriteLine(b);//3

第三种方法：

0000003a  mov         dword ptr [ebp-40h],14h
00000041  mov         dword ptr [ebp-44h],0Ah
low = high + (high = low) * 0的反汇编是这样的：
00000048  mov         eax,dword ptr [ebp-40h]
0000004b  mov         dword ptr [ebp-48h],eax      //这里是第三个变量地址
0000004e  mov         eax,dword ptr [ebp-44h]
00000051  mov         dword ptr [ebp-40h],eax
00000054  mov         eax,dword ptr [ebp-48h]
00000057  mov         dword ptr [ebp-44h],eax