use warnings;
use strict;

my @my_arr=(
[1,    11,    0,    0],
[12,    109,    0,    0],
[16,    1,    16,    0],
[14,    14,    2,    0],
[45,    16,    5,    4]
);

my ($index1, $index2) = (5, 4); #used 1-based index for easy communication
while (1) {
	last if $index1 > 5 || $index1 < 1 || $index2 > 4 || $index2 < 1;
	print $my_arr[$index1 - 1][$index2 - 1], "\n";
	$index1 = $my_arr[$index1 - 1][$index2 - 1];
	$index2 --;
}