use strict;
use warnings;

while (<DATA>) {
   my @cols = split;
   shift @cols;
   my $all_r = 1;
   for my $c (@cols) {
      if ($c ne 'r') {
         $all_r = 0;
         last;
      }
   }
   print if $all_r;
}

__DATA__
0  a b h
1  - r z
3  u - u
4  r x r
5  r t r
6  r r r
7  r r r
8  r r r

[download]

prints out: 

6  r r r
7  r r r
8  r r r

[download]

update: even better with List::MoreUtils: 

use strict;
use warnings;
use List::MoreUtils qw(all);

while (<DATA>) {
   my @cols = split;
   print if all { $_ eq 'r' } @cols[1 .. $#cols];
}

__DATA__
0  a b h
1  - r z
3  u - u
4  r x r
5  r t r
6  r r r
7  r r r
8  r r r

[download]

In reply to Re: Count similar characters in a row by toolic
in thread Count similar characters in a row by $new_guy

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