open DATA, "<", $ARGV[0];
my @p;
<DATA>;
while (<DATA>) {
    chomp;
    if (m/^(\d+?) (\d+?)$/) {
        push @p, [$1, $2];
        next;
    }
    if (m/^\d+?$/) {
        my $min = 10_000;
        for my $tgt (0..$#p) {
            for ($tgt+1..$#p) {
                my $d = (($p[$tgt][0] - $p[$_][0])**2 + ($p[$tgt][1] - $p[$_][1])**2)**.5;
                $min = $d if ($d < $min);
            }
        }
        print $min < 10_000 ? sprintf "%.4f\n", $min : "INFINITY\n";
        @p = ();
    }
}