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import java.util.Scanner;
public class Permutations {
// print N! permutation of the characters of the string s (in order)
public static void perm1(String s) {
perm1("", s);
}
private static void perm1(String prefix, String s) {
// System.out.println("prefix: " + prefix);
// System.out.println("s: " + s);
int N = s.length();
if (N == 0) System.out.println(prefix);
else {
for (int i = 0; i < N; i++)
perm1(prefix + s.charAt(i), s.substring(0, i) + s.substring(i + 1, N));
}
}
// print N! permutation of the elements of array a (not in order)
public static void perm2(String s) {
int N = s.length()-1;
/*
char[] a = new char[N];
for (int i = 0; i < N; i++)
a[i] = s.charAt(i);
*/
char[] a = s.toCharArray();
perm2(a, N);
}
private static void perm2(char[] a, int n) {
if (n == 0) {
System.out.println(a);
return;
}
for (int i = 0; i