a1_2 a1_1 a10_10 a2_10 a2_1 a2_2 a10_1 a10_2 a1_10

##</code><code>##

a1_1 a1_2 a1_10 a2_1 a2_2 a2_10 a10_1 a10_2 a10_10

##</code><code>##

use strict;
use warnings;

open(INPUTFILE, "< ccc");
my @list = <INPUTFILE>;
my $newlist=$list[0].$list[1].$list[2];
my @split_list = split(" " ,$newlist);

my @new_list = sort {
  
   ($a =~ /(\d+)/)[0] <=> ($b =~ /(\d+)/)[0] 
    	            ||
   ($a =~ /(\w+)/)[0] cmp ($b =~ /(\w+)/)[0]
   		   
} @split_list;

print "@new_list\n";