/**
* 定义两个变量 在不定义第三个变量的情况下交换两个变量的值
*/
public class jiaoHuan {
public static void main(String[] args) {
String s1 = "00";
String s2 = "abcd";
System.out.println("交换之前 s1 = " + s1 + " s2 = " + s2);
s2 = s1 + s2; //合并到s2
System.out.println("s2 = " + s2); //00abcd
s1 = s2.substring(s1.length());
//截取前面长度为4的字符串 s1 = "abcd"
s2 = s2.substring(0, s2.length() - s1.length());
//截取最后长度为2的字符串 s2 = "00"
System.out.println("交换后 s1 = " + s1 + " s2 = " + s2);
}
}
/**
* int类型
*/
class testInt {
public static void main(String[] args) {
int a = 1;
int b = 9;
System.out.println("交换之前 a = " + a + " ,b = " + b);
a = a + b;
b = a - b;
a = a - b;
System.out.println("交换之后 a = " + a + " ,b = " + b);
}
}