變量值a交換b，b交換a....

package day01;  
  
public class Test1 {  
    public static void main(String[] args) {  
        //不利用其它變量時期A和B的值交換  
        Integer A=1;  
        Integer B=2;  
          
        //  
        fun1(A, B);  
          
        //異或  
        fun3(A, B);  
    }  
    public static void fun1(Integer a,Integer b){  
        a=a+b;  
        b=a-b;  
        a=a-b;  
        System.out.println("A="+a+",B="+b);  
    }  
    //異或實現兩個數據交換  
    public static void fun3(Integer A,Integer B){  
        A=A^B;  
        B=A^B;//A^B^B=A  
        A=A^B;//A^B^A=B  
        Syst