不使用第三个变量完成两个整数的交换

 public class Person {   
  
    public static void main(String[] args) {   
        //利用加减法   
        int a = 10, b = 5;   
        a = a + b;   
        b = a - b;   
        a = a - b;   
           
        System.out.println("a=" + a + "\nb=" + b);   
    }   
}  

还有另外一种方法，且效率更快：

public class Person {   
  
    public static void main(String[] args) {   
        //利用一个数异或本身等于０和异或运算符合交换率   
        int a = 10, b = 5;   
        a = a ^ b;   
        b = a ^ b;   
        a = a ^ b;   
           
        System.out.println("a=" + a + "\nb=" + b);   
    }   
}