Permuting using any number of given chars

[Brian Wakem]

I can use Algorithm:ermute to output all permutations of 1 2 3

123
132
312
213
231
321


But what I'm looking for is all possible permutations using any number of
the input chars.

Like this -

1
2
3
12
13
21
23
31
32
123
132
312
213
231
321


I can't think of a way right now and I can't find a module that does it.
Any ideas?

 

[Anno Siegel]

I can use Algorithm:ermute to output all permutations of 1 2 3

123
132
312
213
231
321


But what I'm looking for is all possible permutations using any number of
the input chars.

Like this -

1
2
3
12
13
21
23
31
32
123
132
312
213
231
321


I can't think of a way right now and I can't find a module that does it.

Split the problem. You know how to get all permutations for a given
set. So find all subsets of the input characters ('', '3', '2', '23', '1',
'13', '12', '123') and apply your solution to each.

for ( subsets( '123') ) {
print_permutations( $_);
}

The definition of subsets() is left as an exercise in recursion.

Anno