On Dec 11, 2007, at 9:53 PM, ciwei2103 wrote:
Give a disk sequence know that is incrementing with base 16, such
as ,
0001
0003
0004
0008
0009
000A
000B
000F
0010
0011
how do I extract the a subset that is have at least 4 consecutives,
such as "0008 0009 000A 000B"
I hope this has to do with backups and not homework:
use strict;
use warnings;
use constant AT_LEAST_THESE_MANY => 4;
my @disks = qw(
0001
0003
0004
0008
0009
000A
000B
000F
0010
0011
);
my @codes = map hex, @disks;
my $start;
my $nsucc = 0;
for (my $i = 0; $i < $#codes; ++$i) {
my $diff = $codes[$i+1] - $codes[$i];
if ($diff == 1 && $i + 1 < $#codes) {
++$nsucc;
} elsif ($nsucc + 1 >= AT_LEAST_THESE_MANY) {
$start = $i - $nsucc;
last;
} else {
$nsucc = 0;
}
}
print "@disks[$start..($start+$nsucc)]\n" if $start;
-- fxn
--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
http://learn.perl.org/
