// CSE 143, Winter 2012
// This program contains some methods we implemented to manipulate ArrayLists.

import java.util.*;

public class Friday {
	public static void main(String[] args) {
		ArrayList<Integer> list = new ArrayList<Integer>();
		list.add(42);
		list.add(-17);
		list.add(25);
		stutter(list);
		System.out.println(list);
		
		ArrayList<String> words = new ArrayList<String>();
		words.add("the");     // 0
		words.add("quick");   // 1
		words.add("brown");   // 2
		words.add("fox");     // 3
		
		System.out.println(words);
		addStars(words);
		System.out.println(words);
	}

	// Adds a "*" after each element of the given list.
	// For example, [hi, ok, bye] becomes [hi, *, ok, *, bye, *].
	public static void addStars(ArrayList<String> words) {
		for (int i = 1; i <= words.size(); i += 2) {
			words.add(i, "*");
			System.out.println(words);
		}
	}
	
	// Replaces every element in the list with two occurrences of itself.
	// For example, [4, -2, 17] becomes [4, 4, -2, -2, 17, 17].
	public static void stutter(ArrayList<Integer> list) {
		for (int i = 0; i < list.size(); i += 2) {
			list.add(i, list.get(i));
		}
	}
}