交换（四种交换方式）（反转字符串）

1. 中间temp

    temp = a;
    a = b;
    b = temp;
   
   

2. 相加减

    a = a + b;
    b = a - b;
    a = a - b;
   

   或

   a = a - b;
   b = a + b;
   a = b - a;
   

3. 位操作

   a = a ^ b;
   b = a ^ b;
   a = a ^ b;
   

标签：位操作,temp,相加,交换,字符串,四种
来源： https://www.cnblogs.com/FL-nono/p/15711064.html