// see bottom of page 402 of Savitch
// This is an example that I wish he gave -- his explanation of Java's
// behavior in passing an array and changing its contents is unclear. 
// A method can change an object's variables. Since an array is an object
// with elements acting like instance variables, a method may change the
// values stored inside an array.

public class savitch402 {

    public static void main(String[] args) {
	int[] a = {1,2};
	print(a);
	doStuff(a);
	print(a); 
	// Is $a$ changed? No! $a$ still refers to an array.
	// Are the contents of $a$ changed? Yes!
    }

    public static void doStuff(int[] x) {
	print(x);
	x[0]=3;
	x[1]=4;
	print(x);
    }
    
    public static void print(int[] x) {
	for (int i = 0; i<x.length; i++)
	    System.out.print(x[i] + " ");
	System.out.println();
    }

}

/* output
   1 2 
   1 2 
   3 4 
   3 4 
*/