#! perl -slw
use strict;
use Data::Dumper;

# create matrix
#
# [
#    [ a, b, c, d ],
#    [ e, f, g, h ],
#    [ i, j, k, l ],
#    [ m, n, o, p ],
# ]

my $a = 'a';
my @a2d = map{ [ map{ $a++ } 1..4 ] } 1..4;

#print Dumper \@a2d;


for my $y ( 0, 2 ) {
    for my $x ( 0, 2 ) {
        print @{ $a2d[ $y   ] }[ $x .. $x+1 ];
        print @{ $a2d[ $y+1 ] }[ $x .. $x+1 ], $/;
    }
}
__END__
ab
ef

cd
gh

ij
mn

kl
op
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