两个整数交换，不引入第三个参数

有两种方法：

public class Test {

    public static void main(String[] args) {

        method1();
        method2();
    }

    private static void method1() {

        int a = Integer.MAX_VALUE;
        int b = Integer.MIN_VALUE;

        System.out.println("交换前" + a + "," + b);
        a = a + b;
        b = a - b;
        a = a - b;
        System.out.println("交换后" + a + "," + b);
    }

    private static void method2() {

        int a = Integer.MAX_VALUE;
        int b = Integer.MIN_VALUE;

        System.out.println("交换前" + a + "," + b);
        a = a ^ b;
        b = a ^ b;
        a = a ^ b;
        System.out.println("交换后" + a + "," + b);
    }
}

 结果：

交换前2147483647,-2147483648
交换后-2147483648,2147483647
交换前2147483647,-2147483648
交换后-2147483648,2147483647