Woo-hoo! More Hofstadter fans!

Strangely, the 9 10 digit problem is solvable without using genetic algorithms or any randomization functions. Here's a solution that just starts with each count at 0 and feeds the last counts into the next sentence, evaluates, and repeats until the sentence is truthful: 

#!/usr/bin/perl
use strict;
use warnings;

my @list = 0..9;
my %hash;
$hash{$_} = 0 for @list;
my $valid = 0;
my $test = '';
while (!$valid) {
    $valid = 1;
    $test = 'This sentence contains ';
    $test .= "$hash{$_} ${_}s, " for @list;
    $test .= '. - ';
    print $test;
    my %test_hash;
    for (@list) {
        $test_hash{$_} = eval("\$test =~ tr/$_//");
        $valid = 0 if ($hash{$_} != $test_hash{$_});
        $hash{$_} = $test_hash{$_};
    }
    ($valid == 1) ? print "yes\n" : print "no\n";
}

[download]

I won't spoil this by printing the answer, but it only took 4 iterations to achieve.

In reply to Re: Improving Evolutionary Algorithm by delirium
in thread Improving Evolutionary Algorithm by jweed

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