diff --git a/day06/day06.pl b/day06/day06.pl
new file mode 100644
index 0000000..ca32844
--- /dev/null
+++ b/day06/day06.pl
@@ -0,0 +1,56 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+use feature qw/ say /;
+use Test::More;
+
+ok( start_of_packet_marker("mjqjpqmgbljsphdztnvjfqwrcgsmlb") == 7 );
+ok( start_of_packet_marker("bvwbjplbgvbhsrlpgdmjqwftvncz") == 5 );
+ok( start_of_packet_marker("nppdvjthqldpwncqszvftbrmjlhg") == 6 );
+ok( start_of_packet_marker("nznrnfrfntjfmvfwmzdfjlvtqnbhcprsg") == 10 );
+ok( start_of_packet_marker("zcfzfwzzqfrljwzlrfnpqdbhtmscgvjw") == 11 );
+ok( start_of_message_marker("mjqjpqmgbljsphdztnvjfqwrcgsmlb") == 19 );
+ok( start_of_message_marker("bvwbjplbgvbhsrlpgdmjqwftvncz") == 23 );
+ok( start_of_message_marker("nppdvjthqldpwncqszvftbrmjlhg") == 23 );
+ok( start_of_message_marker("nznrnfrfntjfmvfwmzdfjlvtqnbhcprsg") == 29 );
+ok( start_of_message_marker("zcfzfwzzqfrljwzlrfnpqdbhtmscgvjw") == 26 );
+done_testing();
+
+sub start_of_packet_marker {
+    my $datastream = shift;
+    my $marker     = 4;
+    while ( !is_start_packet( substr( $datastream, ( $marker - 4 ), 4 ) ) ) {
+        $marker++;
+    }
+    return $marker;
+}
+
+sub is_start_packet {
+    my $packet = shift;
+    my %packet = map { $_ => 1 } split( //, $packet );
+    keys %packet == 4 ? return 1 : return 0;
+}
+
+sub start_of_message_marker {
+    my $datastream = shift;
+    my $marker     = 14;
+    while ( !is_start_message( substr( $datastream, ( $marker - 14 ), 14 ) ) ) {
+        $marker++;
+    }
+    return $marker;
+}
+
+sub is_start_message {
+    my $packet = shift;
+    my %packet = map { $_ => 1 } split( //, $packet );
+    keys %packet == 14 ? return 1 : return 0;
+}
+
+open( my $fh, "<", "input" )
+    or die "Can't open < 'input': $!";
+
+my $line = <$fh>;
+
+say start_of_packet_marker($line);
+say start_of_message_marker($line);
\ No newline at end of file
diff --git a/day06/input b/day06/input
new file mode 100644
index 0000000..6a49340
--- /dev/null
+++ b/day06/input
@@ -0,0 +1 @@
+qvllndllhzhfzhhdzhddhjdjggvnvhvccmffwllqgqmmfjfqfhhtrrzczjczzlplddfpptqqfbqffmnmjnnqppfjfccgnnmqqsvvdbbgppjvpjvpjjctjjttwtrrdldlcddrvddqndqnqwqwzwfwwzczggcppgzpzhpzhppprfffbhhwmhhtftstrsrvsrvsrvvshvssnwwpllhfhnnfflcltlblzlqlvqlvlcldcccpptggtdgdjdbbrggmbmnncscbssqrrjddvcvgvfflpppgpvphvphhpcpzpzvvctvctvthtwtfwwbrrhhlplmlwwlqlnlhhtmhmmqlqplllrvrgvrvrffzfgfjfjtjmjvmjmwmvvjffmpfphfhvfvmfvmmhpphhltthgttgccqggpzpfpqpcpvcpvcvvqtqvqbbrlrtllmrmllhmhvmhhvzhvzvrrrzjzbbtvvbgvbbfnnqndqnnpnbnbnlnggwqggmgmqmgmbbmccgqcqbccpvcvnnhvvrvlrrcwrcwrcwrwbrwwzbwbdbfddpttntzzjszsnznbndnzngzgccjrcjchcffmlmqqlrqqzsqzzsbsnsttzpztpzpggzrrttbqqplpqlqjjqcqvccdzdccthccvfcvvqvhqhfhhzwzpzwppgpttntssflfjjrwrqrjrppptlltptpvttpfpwpswpppzzsrzssqllbnlljpllrjllsrlrhrdrmdrmrrpsrprnrffgrffdqdhdqhhrhggwqqlddsbsqbqtqdtdhdvhhbdhdzhdhhtrrppzddgfgzgpzpvpfpnpptggltggbnbppqffzfrzzzsbsrrdgrddwsdsqddhpdpbpvpfvppfsfgfngffzmzbzlblclsccvqvqmmjtjqtjjlcjllsddjqddhldlvlrrbgbrgbrrdzzpfpggqnqbqrrqbbgjgppqgpgwgqqndncndnpdnnbvbnvnwnjjgppzlplqqdgqghqgqzggjssqmmwwcfcpptrpprggrppgbplmzwmdtnpqwzcrthqbppwbgcvgqrpfpnbscnhvrllpvpqwnsslcjrqtvdccprvqfrpswtpvzdzlgtmmvppdmhgdbbsmrbqpqspdhpqgfjznqzphrnggcbzhdqrgvzcfzrhtrlssgmjjghqsjtghhnwjffqrrfslfnsvvdvfjqbfpffrrstdhggvbfwtfpfgswqlfdrnjpjmwzptlbmwgghgwqrphcrvfmhrplllgbnjlprllmjwccphsflntgpnbmdbfqcdsbgvrnfznfrlcfvswqfrqvdnbjsflnsmlcrdstzppmcvbgdtcvgztbdzqbwhmwcfvbwjjcdgbnwjwzrrdqhpgscwtnztjsfstzfwftcldjgvdvwbzrlbdslwttbqpnlwbjcjwqgtrgcglsgtdqbqbnqznptzzbwffwlwzvvtdpcjbvhnswzptclpbndcdvsfmcrmwwgzdfsszqjjdztmtsqgfqzjpctfdpwnzbpnzzwngqnghntblndfrnjzdrmgbqmzbdqfzctrgshwqgfgqssqjltrqlzjswjhmpgwwjdwcjpnsvgrvbfpmlmmwzmbdjwsrjthppfrccjgnmwlvqlprgslbwtbbzlqbznczmsmhsfdcqnwblprcpbzzwfllbnldvpjcwsdhglrzjsptmsjdjqzsmgvhjfjrrtvvbjlmzjsntnrggwbpjlrjggfgqzvswtggthzfmfjnmrzrttbzqpwpsnmdtnbfblpfgslgcmjlbdpshnnrbhvwsbrnvdmjqhvhdjhbfzjmqrmqmdthhzvnrmqcnbtwcdjdqfvdgvmfbhrfqnmdncrddggtcppjlznbsnntppjtnsqsrjwvfrzpnzqcrzhhdflfmmtmwcvtpzbqhdwsczffcqhtdbdjblmgnrmhlqcsvcpgghhvwqhdtzpzlpfllchzltqgcwgfqnbzhgzmdwqdlwnvhqmpqjqnjbhjctslghdqvctdmjfwdfpdjnhdndzwsfjzlmsbmfmzvnvpqgqhtngvgqmlrrzsfmwlcwsscvghjvrzjjqbnplnjzqswpblwzwczhwbhhnjmctnmwlbqqfmnlwdcrptlmfjpjrnpcvmhffjhwhmntdzpdjzwzhrrsdvmjlwdtcpvjfmfzfsrgjghhlvmjjjczgmhvrfpgqbnhldwbrjgzmnszzbssfzcggrwmdfvddwsdmnwtwfwlfnwlvzlctfblbtrjvcwjjdljplcrjhwqslppwwtvfqwsjlfmdznmcdzdmgvmmsrfcclcvhtrhlsjzrbjwrjlfnvqhqvmpzmdttnbhfcvnqlrqbcsvtvwfccjstjpmhqgwlnrzjjmfdszflmglrdbpqhqhqsdfzrcljbdvvnlcqfllmnqcjfzjppdsjwshfschzqbnwfqnpwhqnmwsjbtcgvrljsrtzvcvghcjjlqsngglcggqpntrrhbjpbfhmvpltmnfmfdtwnczwfbvjcqnhvppjftwvwsrlhvvcjtsfptpqgrmrqwwddnqmnmfgrlnphbpqhhhvglqgtwvnwvnbssftmwttmfrffwtzhrpqspclvgchwqwcsgwqwwvpgcwngrcfmhbhflwfbfchlphdzdcrflfmfclsngtlwrqcrsgrdzcpdsvvcdbhgtljmbntbbcqgjqfsbfwzlfsnljpjdcnmjlqrwpmlvwgdlrrdgfhdqhzgltmclzgzzhmrbggsmgtpqdrgmjtlzwstrwbpvhppvsmdqvvwwglzjgdswjszqmrdbmshbhhcstpcsjdbvgjnvcmvhbtclrlmlgnvppgvncsrfchdbqjrclwwlnchmcgvshfsbsvvcvjrsgjlnsfqtqmgntffwnqjtldcqbcqhsgztllstswwqnfrswpchqhnfzzzszqjztzfrgrbjdbjlpvqfqrlrmmpbfbbcclrgmnlzwqrjhqrstswjpgsrtnlwsbqthzpvdzllzqmdmbvvtcztftvlwphhjzbfnrvccfmhmvmzlbrzlnppfzcsffjvjmbgpvlwgwszpztjpsrbnftqtdrbnljtbrjzzbwlsvtwtlwptdtnmtncvcblcmdngjzmctlqtzchncccnwjzrrmmmnllbhrnhwtqjsnvcslrqjfbfndqvdlrjshdzmlprtzbtnhthdqhplwzdbnjmgzlzrbzrvrqnflwfmsmbssqnbcddnvdpltpmplpdzvtjrslcdcnrdplwtjtvctwfzhlvwwqqtbqcjjwhhnpmvgzhqmqfgthwbphrmrtdghchsmwghdqjgjgmpddbrtngtvhqgjfrplrdgpbnhqvswrmqhcmsqvsqmqsgwjndwjrbrhvrctmmrmfwpsgfgdlrzpslpflgvwrgcthgcrnhgrzsmqdgdssjgspfhmqfmjfpmwqhnfjdvqzhpndvnbmqglbrjmdrwgmgctrgzpsdvfbmcstcslblmvnprphntgslmlrqwthrndrhtbccgzzfsglhgqztcsnqjwfzbzlvrpbvswbhrwdsrhrrpnrmsbvbvjccbdsdcfrrzpgwjtnnnvjwlcppwzdqsbdzpfjplrlfgvjpsmbzwpwlghnvqgddfjvrsztrpzlfgmqqzrfcgglghndbhgbmldglclhldljjdslvhzshshtqwhqnbzhvqrcmwdmcmhjcrmdmhrwnwcbhvbbrwrbtfdnztwnbpdfjfhgrmcpngftsvbsmsptnwcvvllnmbnsntbzmwnhfdptbtzswtjzdqwjdhprnjwvhzpscjvlsgrhdrmmrmhzhwwtslzdjqmzfncnmgplhnmwrvqhslvchtjcmpzpjpnpfbjptvvwcsmhgdjtsqrjlfpnfdncpqqmpgpvtlvwljlsqbnhtsqgfwlsmdjpgtvgjvjcrnnzmbllqzlrfdnlffgmtphhhgbcjgdlpzqpwmjwtcmdrsmtnmddftwczbsddtppsptbwfvpnfnsqmsgcfqfmnzffzqgcdvwzrgdwhmnzmrlhcdpdsltnsmjzdqwmmpwvjqbbwsrfgzh