import java.util.Scanner;import java.util.Vector;public class Question1 { public static int total = 0; PRivate static Scanner scanner; private void prem(Vector<Character> source, Vector<Character> result) { if (source.size() == 0) { for (int i = 0; i < result.size(); i++) { System.out.print(result.elementAt(i)); } System.out.println(); total++; return; } for (int i = 0; i < source.size(); i++) { Vector<Character> tsource = new Vector<Character>(source); Vector<Character> tresult = new Vector<Character>(result); tresult.add(tsource.elementAt(i)); tsource.remove(i); new Question1().prem(tsource, tresult); } } public static void main(String[] args) { scanner = new Scanner(System.in); int n = scanner.nextInt(); Vector<Character> source = new Vector<Character>(); Vector<Character> result = new Vector<Character>(); for (int i = 0; i < n; i++) { source.add((char) ('A' + i)); } new Question1().prem(source, result); System.out.println(total); }}
