#!/usr/bin/perl -w
use Strict;

$dat = "a.txt";
open(DAT, "$dat") || die "Can't open the file.\n";
@a=<DAT>;
close(DAT);

my $temp3;

foreach (@a) {chomp $_; $temp3 .= "$_ "}

@a = split(/.,;/, $temp3);

foreach (@a) {$_ .= "\n";}

print @a;