$b = "abefcdghijklmn" ;

$a[0]->[0] = "start 0" ;
$a[1]->[0] = "start 1" ;

my @b = unpack 'A' x 14, $b;

while (@b) {
    push @{$a[0]}, shift @b;
    push @{$a[1]}, shift @b;
}

foreach ( @{$a[0]} ) {
    print "$_\n" ;
}
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