use warnings;
use strict;
use Data::Dump;

my @trip = ("Chicago", "Saint Looey", "Joplin", "OKC", "Amarillo",
	"Gallup", "Flagstaff", "Winona", "Kingman", "Barstow",
	"San Bernandino", "LA");

my %cities = ( "Amarillo" => { state => "TX" },
	"Barstow" => { state => "CA" }, "Chicago" => { state => "IL" },
	"Flagstaff" => { state => "AZ" }, "Gallup" => { state => "TX" },
	"Joplin" => { state => "MO" }, "Kingman" => { state => "AZ" },
	"LA" => { state => "CA" }, "OKC" => { state => "OK" },
	"Saint Looey" => { state => "MO" },
	"San Bernandino" => { state => "CA" },
	"Winona" => { state => "AZ" }, );

for my $i (0..$#trip-1) {
	my ($from,$to) = @trip[$i,$i+1];
	print "$from, $cities{$from}{state} to $to, $cities{$to}{state}",
		$cities{$from}{state} ne $cities{$to}{state}
			? " - Mann Act!" : (), "\n";
}

print "\n##### Alternative #####\n";

$cities{$_}{city} = $_ for keys %cities;
$_ = $cities{$_}//die("bad city $_") for @trip;
dd \%cities, \@trip;

for my $i (0..$#trip-1) {
	my ($from,$to) = @trip[$i,$i+1];
	print "$from->{city}, $from->{state} to $to->{city}, "
		."$to->{state}", $from->{state} ne $to->{state}
			? " - Mann Act!" : (), "\n";
}