Hi,

I am trying to solve day 8, part a. of Advent of Code: https://adventofcode.com/2022/day/8 . I am being flooded with uninitialized value warnings for lines 52, 55, 72, and 75. Here is one:

Use of uninitialized value in numeric lt (<) at ./day8a-l.pl line 55, <$line> line 98

My input is 99 lines with 99 numbers ranging from 0-9 on each line(no whitespace). Here is my code:

#!/usr/bin/perl

use strict;
use warnings;

my @row;
my $current = 0;
my $visible = 198;
my $found = 0;

open(my $lines, '<', 'input8.txt');

foreach (<$lines>)
{
    chomp;
    for my $l (0..length()-1)
    {
        my ($digit) = /^.{$l}(.)/;
        if (defined $digit)
        {
            $row[$current][$l] = $1; 
        }
    }
    $current += 1;
}

close $lines;
open(my $line, '<', 'input8.txt');

$current  = 0;

while (<$line>)
{
    chomp;
    if ($current > 0 and $current < 98)
    {
        $visible += 2;
        for (my $i = 1; $i < 98; $i++)
        {
            my $counter = 1;
            $found = 0;
            while ($row[$current][$i-$counter] < $row[$current][$i] an
+d $found == 0)    
            {
                $counter += 1;
                if ($counter == $i)
                {
                    $visible += 1;
                    $found = 1;
                    $counter = 1;
                }
            }
            while ($row[$current][$i+$counter] < $row[$current][$i] an
+d $found == 0)
            {
                $counter += 1;
                if ($counter == $i)
                {
                    $visible += 1;
                    $found = 1;
                    $counter = 1;
                }
            } 
            while ($row[$current-$counter][$i] < $row[$current][$i] an
+d $found == 0)
            {
                $counter += 1;
                if ($counter == $current)
                {
                    $visible += 1;
                    $found = 1;
                    $counter = 1;
                }
            }
            while ($row[$current+$counter][$i] < $row[$current][$i] an
+d $found == 0)
            {
                $counter += 1;
                if ($counter == $current)
                {
                    $visible += 1;
                    $found = 1;    
                    $counter = 1;
                }
            }
        }
    }
    $current += 1;
}
close $line;

print $visible . "\n";
[download]

I'd be really grateful for any suggestions. Thanks,

L

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