{% highlight java %} def permutation(String input){ permutation("", input); }
def permutation(String perm, String word) { if (word.isEmpty()) { println(perm + word);
} else {
for (int i = 0; i < word.length(); i++) {
permutation(perm + word.charAt(i), word.substring(0, i)
+ word.substring(i + 1, word.length()));
}
}
}
permutation(“123”) {% endhighlight%}