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import java.util.Arrays;
import java.util.HashMap;
import java.util.Set;

public class Main {
	static void permut(String[] words) {
		//zählen, welches Wort wie oft vorkommt
		HashMap<String, Integer> dict = new HashMap<String, Integer>();
		for (String word : words) {
			if (!dict.containsKey(word)) {
				dict.put(word, 0);
			}
			dict.put(word, dict.get(word) + 1);
		}
		//Permutationen bilden
		permutRecurs(dict, dict.keySet(), 0, new String[words.length]);
	}

	static void permutRecurs(HashMap<String, Integer> wordCount, Set<String> keys, int index, String[] sequence) {
		//Alle Wörter verwendet?
		if (index == sequence.length) {
			System.out.println(Arrays.toString(sequence));
		}
		for (String word : keys) {
			//noch ein Wort übrig?
			if (wordCount.get(word) > 0) {
				wordCount.put(word, wordCount.get(word) - 1); //Wort als verwendet markieren
				sequence[index] = word; //und Position des Wortes speichern
				permutRecurs(wordCount, keys, index + 1, sequence); //rekursiver Aufruf
				wordCount.put(word, wordCount.get(word) + 1); //nach der Rekursion Wort wieder zur Verwendung freigeben
			}
		}
	}

	public static void main(String[] args) {
		permut(new String[] { "Matse", "Milch", "Nett", "Ungarn", "Matse", "Milch", "Nett", "Ungarn" });
	}
}