Re: Re (tilly) 1: (Golf) Fragment Reassembly

[MeowChow]

I had considered explicitly stating that solutions such as yours, which iterate through all possible strings, would be rated in a seperate class. This makes me wonder, however, if there is a class of optimization problems for which iterating brute-force through the entire solution space is faster (algorithmically) than directly computing a solution.

You are a bit mistaken in choosing Golf: Embedded In Order, however, since that is not the same thing as a substring:

print assemble(qw(oa af wf wa));

# owaf - a wrong answer
# oafwfwa - a right answer

If you change that into an index, things work out bettter (and with less code):

sub c{@r='';@r=map{$c=$_;map$c.$_,@r}@_ for 1..shift;@r}

sub assemble {
my$n;{for(c($n++,map{split//}@_)){$v=$_;map{1+index$v,$_ or next}@_;re
+turn$_}redo}
}

print assemble(qw(oa af fa afa));

   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

[tilly]

Oops, my misreading.

As for the question, there actually are well-explored areas where the best known algorithms (by various criteria) are found by randomly guessing something with certain characteristics and then testing whether it really was a solution...