#!/usr/bin/perl

use strict;
use warnings;

use 5.010;

my @rows = <DATA>;

print "\n1. Loesung:\n";
print s/(\S+\s+\S+)\s+(\S+)/$1       $2/r for @rows;

print "\n2. Loesung:\n";
print s/ +/\t/gr for @rows;

print "\n3. Loesung:\n";
printf "%s\t%s\t%s", split / +/ for @rows;

__DATA__
xxxxx yyyyyy zzzzz
xxxxx yyyyyy    zzzzzzz
xxxxx yyyyyy       zzzzzz