public class Swap
{	 
  	public static void main (String[ ] args) 
  	{    
    		double[ ] x = {5.0, 8.0, 12.2, 20.0};
        		         
    		swap (x, 1, 2);
    
    		System.out.println (x [1] + " " + x [2]);
	} // method main


	public static void swap (double[ ] a, int i, int j)
  	{
      		double temp = a [i];
      		a [i] = a [j];
      		a [j] = temp;
  	} // method swap

} // class Swap