在 Java 中不使用多余变量交换两个字符串

在 Java 中不使用多余变量交换两个字符串

public class Test {
    public static void main(String[] args) {
        String a = "Hello";
        String b = "World";
        System.out.println("Strings before swap: a = " + a + " and b = " + b);

        a = a + b;
        b = a.substring(0, a.length() - b.length());
        a = a.substring(b.length());

        System.out.println("Strings after swap: a = " + a + " and b = " + b);
    }
}

Strings before swap: a = Hello and b = World
Strings after swap: a = World and b = Hello