#!/usr/bin/perl -w
use strict;
my$line;
my@fields;
my@output;
open (FILE, 'XXXX.txt') or die "can't open the file: $!";
open (FD, '>XXXX.txt') or die "can't open the file: $!";
while (defined ($line= <FILE>)) {
my@fields= split (/\s/ ,$line);
my@output = grep /rs\d{5,}\b/ ,@fields;
my$rs = join (':' , @output);
$rs=~ s/:/\n/g;
print FD "$rs";
}
close FILE;
close FD;