#! /usr/bin/perl

$n = &readarray;

$smooth = 3;
$smooth = $ARGV[0] if $ARGV[0];
$nsmooth = 2 * $smooth + 1;

for ($i = $smooth; $i < $n-$smooth; $i++) {
	$sum = 0;
	# print "$i\n";
	for ($low = $i - $smooth; $low <= $i+$smooth; $low++) {
		$sum += $array[$low];
		# print "	$low $array[$low]\n";
	}
	$mean = $sum / $nsmooth;
	print $i+1, "	", $mean, "\n";
}

sub readarray
{
	local ($n) = 0;
	while (<>) {
		chop;
		for $datum (split (/\D+/, $_)) {
			$array[$n] = $datum;
			$n++;
		}
	}
	return ($n);
}

sub printarray
{
	print "$n items read\n";
	for $i (0 .. $n-1) {
		print "$array[$i]\n";
	}
}