my %game = qw{E 0.0 N 90.0 W 180.0 S 270.0};

for (qw{N E S W}) {
    my $real = (360 + 90 - $game{$_}) % 360;
    printf "game: %s = %5.1f; real: %5.1f\n" => $_, $game{$_}, $real;
}