// CSE 143, Winter 2012
// This program demonstrates usage of an ArrayList to store data. 
// It filters out plurals and prints the words of a file in reverse order.

import java.io.*;
import java.util.*;

public class ReverseFile {
	public static void main(String[] args) throws FileNotFoundException {
		ArrayList<String> words = readFile("words.txt");
		filterPlurals(words);
		printReverse(words);

		// printReverse(readFile("tas.txt"));
	}
	
	// Reads the entire contents of the given file and
	// stores them into a list, which is returned.
	// Assumes that the file exists.
	public static ArrayList<String> readFile(String fileName) throws FileNotFoundException {
		ArrayList<String> words = new ArrayList<String>();
		Scanner input = new Scanner(new File(fileName));
		while (input.hasNext()) {
			words.add(input.next());
		}
		return words;
	}
	
	// Removes all plural words (ones that end with "s")
	// from the given list of strings.
	public static void filterPlurals(ArrayList<String> words) {
		for (int i = 0; i < words.size(); i++) {
			String word = words.get(i);
			if (word.endsWith("s")) {
				words.remove(i);
				i--;
			}
		}
	}
	
	// Prints the elements of the given list, one per line, in reverse order.
	public static void printReverse(ArrayList<String> words) {
		System.out.println(words);
		for (int i = words.size() - 1; i >= 0; i--) {
			System.out.println(words.get(i));
		}
	}
}