AoC 2017 begins

diff --git a/2017/01.pl b/2017/01.pl
new file mode 100755 (executable)
index 0000000..77c9077
--- /dev/null
+++ b/2017/01.pl
@@ -0,0 +1,11 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+chomp (my $data = <>);
+
+$data =~s /\A(.)(.*)\z/\1\2\1/;
+my $sum = 0;
+$sum += $1 while $data =~ /(.)(?=\1)/g;
+say $sum;

diff --git a/2017/02.pl b/2017/02.pl
new file mode 100755 (executable)
index 0000000..6726b6b
--- /dev/null
+++ b/2017/02.pl
@@ -0,0 +1,14 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+chomp (my $data = <>);
+
+my $l = length $data;
+$l /= 2;
+$data .= substr($data, 0, $l);
+$l--;
+my $sum = 0;
+$sum += $1 while $data =~ /(.)(?=.{$l}\1)/g;
+say $sum;

diff --git a/2017/03.pl b/2017/03.pl
new file mode 100755 (executable)
index 0000000..df14649
--- /dev/null
+++ b/2017/03.pl
@@ -0,0 +1,17 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+use List::Util qw(min max);
+
+my $res = 0;
+while (<>) {
+       my @a = split /\s+/;
+       my $m1 = min @a;
+       my $m2 = max @a;
+       $res += $m2-$m1;
+}
+
+say $res;
+

diff --git a/2017/04.pl b/2017/04.pl
new file mode 100755 (executable)
index 0000000..2cd7f4f
--- /dev/null
+++ b/2017/04.pl
@@ -0,0 +1,21 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+use List::Util qw(min max);
+
+my $res = 0;
+while (<>) {
+       my @a = split /\s+/;
+       for my $i (0 .. $#a) {
+       for my $j (0 .. $#a) {
+               next if $i == $j;
+               if (int ($a[$i]/$a[$j])*$a[$j] == $a[$i]) {
+                       $res += $a[$i]/$a[$j];
+               }
+       } }
+}
+
+say $res;
+

diff --git a/2017/05.pl b/2017/05.pl
new file mode 100755 (executable)
index 0000000..f37fa53
--- /dev/null
+++ b/2017/05.pl
@@ -0,0 +1,24 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+my $in = 368078;
+
+my $diam = 0;
+$diam++ while $in > (2*$diam+1)*(2*$diam+1);
+my $dist = 2*$diam-1;
+my $dir = -1;
+my $i = (2*$diam-1)*(2*$diam-1)+1;
+while ($i < $in) {
+       # say "\t$i $dist $dir";
+       if ($dist <= $diam) {
+               $dir = 1;
+       } elsif ($dist > 2*$diam-1) {
+               $dir = -1;
+       }
+       $dist += $dir;
+       $i++;
+}
+
+say $dist;

diff --git a/2017/06.pl b/2017/06.pl
new file mode 100755 (executable)
index 0000000..b22f254
--- /dev/null
+++ b/2017/06.pl
@@ -0,0 +1,44 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+my $in = 368078;
+
+my ($x, $y) = (1, 0);
+my $r = 1;
+$; = ',';
+my %map = ("0,0" => 1);
+sub set {
+       my ($x, $y) = @_;
+       my $sum = 0;
+       for my $dx (-1 .. 1) {
+       for my $dy (-1 .. 1) {
+               $sum += $map{$x+$dx,$y+$dy} if defined
+                       $map{$x+$dx,$y+$dy};
+       } }
+       $map{$x,$y} = $sum;
+               
+       say "$x, $y = ", $sum;
+       exit 0 if $sum > $in;
+}
+
+while (1) {
+       for my $i (0 .. 2*$r-1) {
+               set($x, $y-$i);
+       }
+       $y -= 2*$r-1;
+       for my $i (1 .. 2*$r) {
+               set($x-$i, $y);
+       }
+       $x -= 2*$r;
+       for my $i (1 .. 2*$r) {
+               set($x, $y+$i);
+       }
+       $y += 2*$r;
+       for my $i (1 .. 2*$r) {
+               set($x+$i, $y);
+       }
+       $x += 2*$r+1;
+       $r++;
+}

diff --git a/2017/07.pl b/2017/07.pl
new file mode 100755 (executable)
index 0000000..4950de8
--- /dev/null
+++ b/2017/07.pl
@@ -0,0 +1,18 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+my $valid = 0;
+LINE:
+while (<>) {
+       chomp;
+       my %seen;
+       for my $w (split /\s+/) {
+               next LINE if $seen{$w}++;
+       }
+       $valid++;
+}
+
+say $valid;
+               

diff --git a/2017/08.pl b/2017/08.pl
new file mode 100755 (executable)
index 0000000..4017f65
--- /dev/null
+++ b/2017/08.pl
@@ -0,0 +1,19 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+my $valid = 0;
+LINE:
+while (<>) {
+       chomp;
+       my %seen;
+       for my $w (split /\s+/) {
+               my $w1 = join('', sort split //, $w);
+               next LINE if $seen{$w1}++;
+       }
+       $valid++;
+}
+
+say $valid;
+               

diff --git a/2017/09.pl b/2017/09.pl
new file mode 100755 (executable)
index 0000000..1fc2ca4
--- /dev/null
+++ b/2017/09.pl
@@ -0,0 +1,17 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+
+my $pc = 0;
+chomp (my @offs = <>);
+
+my $steps = 0;
+while ($pc >= 0 && $pc < @offs) {
+       say "$steps $pc $offs[$pc]";
+       $pc += $offs[$pc]++;
+       $steps++;
+}
+
+say $steps;

diff --git a/2017/10.pl b/2017/10.pl
new file mode 100755 (executable)
index 0000000..7aad6f1
--- /dev/null
+++ b/2017/10.pl
@@ -0,0 +1,23 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+
+my $pc = 0;
+chomp (my @offs = <>);
+
+my $steps = 0;
+while ($pc >= 0 && $pc < @offs) {
+       # say "$steps $pc $offs[$pc]";
+       my $off = $offs[$pc];
+       if ($off >= 3) {
+               $offs[$pc]--;
+       } else {
+               $offs[$pc]++;
+       }
+       $pc += $off;
+       $steps++;
+}
+
+say $steps;

diff --git a/2017/11.pl b/2017/11.pl
new file mode 100755 (executable)
index 0000000..1668038
--- /dev/null
+++ b/2017/11.pl
@@ -0,0 +1,27 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+chomp (my @banks = split /\s+/, <>);
+
+my %seen;
+my $steps;
+while (1) {
+       my $key = join(',', @banks);
+       last if $seen{$key};
+       $steps++;
+       my ($max, $maxi);
+       for my $i (0 .. $#banks) {
+               if ($banks[$i] > $max) {
+                       $max = $banks[$i];
+                       $maxi = $i;
+               }
+       }
+       $banks[$maxi] = 0;
+       while ($max--) {
+               $maxi = 0 if ++$maxi > $#banks;
+               $banks[$maxi]++;
+       }
+}
+say $steps;

diff --git a/2017/12.pl b/2017/12.pl
new file mode 100755 (executable)
index 0000000..f9b8b0b
--- /dev/null
+++ b/2017/12.pl
@@ -0,0 +1,32 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+chomp (my @banks = split /\s+/, <>);
+
+my %seen;
+my $steps;
+my $another;
+while (1) {
+       my $key = join(',', @banks);
+       last if defined $another && $another eq $key;
+       if ($seen{$key}++ && !defined $another) {
+               $another = $key;
+               $steps = 0;
+       }
+       $steps++;
+       my ($max, $maxi);
+       for my $i (0 .. $#banks) {
+               if ($banks[$i] > $max) {
+                       $max = $banks[$i];
+                       $maxi = $i;
+               }
+       }
+       $banks[$maxi] = 0;
+       while ($max--) {
+               $maxi = 0 if ++$maxi > $#banks;
+               $banks[$maxi]++;
+       }
+}
+say $steps;

diff --git a/2017/13.pl b/2017/13.pl
new file mode 100755 (executable)
index 0000000..90c7c4b
--- /dev/null
+++ b/2017/13.pl
@@ -0,0 +1,25 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+my %all;
+my %below;
+my %top;
+
+while (<>) {
+       my ($name, $num, $rest) = /^(\w+) \((\d+)\)(.*)/;
+       $all{$name} = $num;
+       next if !length $rest;
+       for my $t ($rest =~ /(\w+)/g) {
+               $below{$t} = $name;
+               $top{$t} = 1;
+       }
+}
+
+for my $node (keys %all) {
+       say $node if !$top{$node};
+}
+
+
+

diff --git a/2017/14.pl b/2017/14.pl
new file mode 100755 (executable)
index 0000000..56740ee
--- /dev/null
+++ b/2017/14.pl
@@ -0,0 +1,48 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+my %all;
+my %above;
+my %top;
+
+while (<>) {
+       my ($name, $num, $rest) = /^(\w+) \((\d+)\)(.*)/;
+       $all{$name} = $num;
+       next if !length $rest;
+       for my $t ($rest =~ /(\w+)/g) {
+               push @{ $above{$name} }, $t;
+               $top{$t} = 1;
+       }
+}
+
+my $start = 'uownj';
+
+sub walk {
+       my ($node) = @_;
+       my %sizes;
+       return $all{$node}
+               if !exists $above{$node};
+
+       my $sum;
+       my %nodes;
+       for my $ab (@{ $above{$node} }) {
+               my $s = walk($ab);
+               $sum += $s;
+               $sizes{$s}++;
+               $nodes{$s} = $ab;
+       }
+       my @sizes = sort { $sizes{$a} <=> $sizes{$b} } keys %sizes;
+       if (@sizes == 1) {
+               return $sum + $all{$node};
+       } else {
+               say $all{$nodes{$sizes[0]}} + $sizes[1]-$sizes[0];
+               exit 0;
+       }
+}
+
+walk('uownj');
+
+
+

diff --git a/2017/15.pl b/2017/15.pl
new file mode 100755 (executable)
index 0000000..9479114
--- /dev/null
+++ b/2017/15.pl
@@ -0,0 +1,31 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+
+my %regs;
+while (<>) {
+       chomp;
+       my ($reg, $op, $val, $creg, $cop, $cval) =
+               /^(\w+) (\S\Sc) (-?\d+) if (\w+) (\S+) (-?\d+)/;
+       $regs{$reg} //= 0;
+       $regs{$creg} //= 0;
+       say "$reg $op $val $creg $cop $cval";
+       if ($cop eq '<' && $regs{$creg} < $cval
+               || $cop eq '>' && $regs{$creg} > $cval
+               || $cop eq '==' && $regs{$creg} == $cval
+               || $cop eq '!=' && $regs{$creg} != $cval
+               || $cop eq '<=' && $regs{$creg} <= $cval
+               || $cop eq '>=' && $regs{$creg} >= $cval) {
+               if ($op eq 'inc') {
+                       $regs{$reg} += $val;;
+               } else {
+                       $regs{$reg} -= $val;
+               }
+       }
+}
+
+use List::Util qw(max);
+
+say max values %regs;

diff --git a/2017/16.pl b/2017/16.pl
new file mode 100755 (executable)
index 0000000..8562c4f
--- /dev/null
+++ b/2017/16.pl
@@ -0,0 +1,35 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+use List::Util qw(max);
+
+my %regs;
+my $max;
+while (<>) {
+       chomp;
+       my ($reg, $op, $val, $creg, $cop, $cval) =
+               /^(\w+) (\S\Sc) (-?\d+) if (\w+) (\S+) (-?\d+)/;
+       $regs{$reg} //= 0;
+       $regs{$creg} //= 0;
+       say "$reg $op $val $creg $cop $cval";
+       if ($cop eq '<' && $regs{$creg} < $cval
+               || $cop eq '>' && $regs{$creg} > $cval
+               || $cop eq '==' && $regs{$creg} == $cval
+               || $cop eq '!=' && $regs{$creg} != $cval
+               || $cop eq '<=' && $regs{$creg} <= $cval
+               || $cop eq '>=' && $regs{$creg} >= $cval) {
+               if ($op eq 'inc') {
+                       $regs{$reg} += $val;;
+               } else {
+                       $regs{$reg} -= $val;
+               }
+       }
+       my $m = max values %regs;
+       $max = $m if !$max || $max < $m;
+}
+
+say $max;
+
+

diff --git a/2017/17.pl b/2017/17.pl
new file mode 100755 (executable)
index 0000000..1a1f1a6
--- /dev/null
+++ b/2017/17.pl
@@ -0,0 +1,21 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+chomp (my $stream = <>);
+
+1 while $stream =~ s/<[^!>]*!./</;
+1 while $stream =~ s/<[^>]*?>//;
+
+my $sum;
+my $depth = 0;
+for my $c (split //, $stream) {
+       if ($c eq '{') {
+               $depth++;
+       } elsif ($c eq '}') {
+               $sum += $depth--;
+       }
+}
+
+say $sum;

diff --git a/2017/18.pl b/2017/18.pl
new file mode 100755 (executable)
index 0000000..88fa689
--- /dev/null
+++ b/2017/18.pl
@@ -0,0 +1,12 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+chomp (my $stream = <>);
+
+my $glen;
+1 while $stream =~ s/<([^!>]*)!./<$1/;
+1 while $stream =~ s/<([^>]*?)>/$glen += length $1/e;
+say $glen;
+

diff --git a/2017/19.pl b/2017/19.pl
new file mode 100755 (executable)
index 0000000..2c5a9cb
--- /dev/null
+++ b/2017/19.pl
@@ -0,0 +1,35 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+my @l = split /[,\s]/, <>;
+
+my $pos = 0;
+my $skip = 0;
+# my @nodes = (0 .. 4);
+my @nodes = (0 .. 255);
+my $n = @nodes;
+
+for my $i (@l) {
+       my $end = $pos + $i;
+       my @to_rev;
+       say "pos=$pos skip $skip i=$i ", join(',', @nodes);
+       if ($end > $n) {
+               push @to_rev, splice @nodes, $pos;
+               push @to_rev, splice @nodes, 0, $end - $n;
+               @to_rev = reverse @to_rev;
+               say "to_rev = ", join(',', @to_rev);
+               unshift @nodes, splice @to_rev, @to_rev-($end-$n);
+               push @nodes, @to_rev;
+       } else {
+               push @to_rev, splice @nodes, $pos, $i;
+               splice @nodes, $pos, 0, reverse @to_rev;
+       }
+       $pos += $i + $skip++;;
+       $pos -= $n while $pos >= $n;
+}
+
+say join(',',@nodes);
+
+say $nodes[0] * $nodes[1];

diff --git a/2017/20.pl b/2017/20.pl
new file mode 100755 (executable)
index 0000000..dadcfa8
--- /dev/null
+++ b/2017/20.pl
@@ -0,0 +1,43 @@
+#!/usr/bin/perl
+
+use v5.30;
+use strict;
+
+chomp(my $line = <>);
+my @l = map { ord } split //, $line;
+push @l, 17, 31, 73, 47, 23;
+
+my $pos = 0;
+my $skip = 0;
+# my @nodes = (0 .. 4);
+my @nodes = (0 .. 255);
+my $n = @nodes;
+
+for (1 .. 64) {
+for my $i (@l) {
+       my $end = $pos + $i;
+       my @to_rev;
+       say "pos=$pos skip $skip i=$i ", join(',', @nodes);
+       if ($end > $n) {
+               push @to_rev, splice @nodes, $pos;
+               push @to_rev, splice @nodes, 0, $end - $n;
+               @to_rev = reverse @to_rev;
+               say "to_rev = ", join(',', @to_rev);
+               unshift @nodes, splice @to_rev, @to_rev-($end-$n);
+               push @nodes, @to_rev;
+       } else {
+               push @to_rev, splice @nodes, $pos, $i;
+               splice @nodes, $pos, 0, reverse @to_rev;
+       }
+       $pos += $i + $skip++;
+       $pos -= $n while $pos >= $n;
+}
+}
+
+my $hash = '';
+while (my @s = splice (@nodes, 0, 16)) {
+       my $x = 0;
+       $x ^= $_ for @s;
+       $hash .= sprintf("%02x", $x);
+}
+say $hash;