public static void main(String[] args) {
      int a = 10;
      int b = 20;
      change(a,b);
      System.out.println("a:"+a+",b:"+b);    //a:10,b:20
}

public static void main(String[] args) {

      int a = 10;

      int b = 20;

      change(a,b);

      System.out.println("a:"+a+",b:"+b);    //a:10,b:20

}

   public static void change(int a, int b) {
      a = b;
      b = a + b;
      System.out.println("a:"+a+",b:"+b);            //a:20,b:40
}
 

   public static void change(int a, int b) {

      a = b;

      b = a + b;

      System.out.println("a:"+a+",b:"+b);            //a:20,b:40

}

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