// Helene Martin, CSE 142
// These methods demonstrate reference semantics for arrays.

import java.util.*;

public class ReverseArray {
	public static void main(String[] args) {
		int[] a = {3, 23, 43, 278, 15};
		
		reverse(a);
		
		System.out.println(Arrays.toString(a));
	}
	
	// given an array of integers, reverse its content
	public static void reverse(int[] a) {
		// need to stop halfway or we undo our work!
		// see jGRASP debugger
		for (int i = 0; i < a.length / 2; i++) {
			swap(a, i, a.length - 1 - i);
		}	
	}
	
	// given an array of integers and two indexes, swap the values
	// at those two indexes
	public static void swap(int[] array, int i1, int i2) {
		int temp = array[i1];
		array[i1] = array[i2];
		array[i2] = temp;	
	}
}