Here's an ugly C-like solution that nevertheless works.

use strict;
use warnings;

my @array;

while ( my $line = <DATA> ) {
    chomp $line;
    push @array, [ split /\s+/, $line ];
}
for ( my $column = 0; $column < @{$array[0]}; $column++ ) {
    for ( my $row = 0; $row < @array; $row++ ) {
        print $array[$row][$column], " ";
    }
    print "\n";
}

__DATA__
1 a x
2 b y
3 c z
[download]