$ perl -e'
use Data::Dumper; 
                  
my $data = <<DATA;
1     2     3
a     p     x
b     q     y
c     r     z
DATA                                                    
                                                        
open my $FH, "<", \$data or die "Cannot open \$data $!";
         
my ( @headers, %hash );
while ( <$FH> ) {
    my @fields = split;
    if ( $. == 1 ) {
        @hash{ @headers = @fields } = ();
        }
    else {
        push @{ $hash{ $_ } }, shift @fields for @headers;
        }
    }

print Dumper \%hash;
'
$VAR1 = {
          '1' => [
                   'a',
                   'b',
                   'c'
                 ],
          '3' => [
                   'x',
                   'y',
                   'z'
                 ],
          '2' => [
                   'p',
                   'q',
                   'r'
                 ]
        };
[download]