Solution for PWC #35 from Burkhard Nickels

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diff --git a/challenge-035/burkhard-nickels/README b/challenge-035/burkhard-nickels/README
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+Solutions by Burkhard Nickels.
diff --git a/challenge-035/burkhard-nickels/blogs.txt b/challenge-035/burkhard-nickels/blogs.txt
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+pearls.dyndnss.net 
diff --git a/challenge-035/burkhard-nickels/perl5/ch-1.pl b/challenge-035/burkhard-nickels/perl5/ch-1.pl
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+#!/usr/bin/perl
+
+use strict;
+use warnings;
+use Text::Morse;
+use Term::ANSIColor;
+use Term::ANSIScreen qw(:color :cursor :screen);
+use Term::Size::Perl qw(chars);
+use Time::HiRes qw(usleep);
+
+=head1 Perl Weekly Challenge #35 Task #1: Text into binary encoded morse code.
+
+This week PWC in Task #1 shall encode text into binary morse code. In this example
+it is done with a Hash Table to translate each letter in a binary string. First all
+unwanted characters are filtered.
+
+I made trials to use Audio::Beep or MIDI::Music to output the Morse code as sound.
+Unfortunately I was not able to get a sound out of my loudspeakers with this two modules.
+They work on OSS, but ALSA is installed and the compatibility modules to OSS did
+not work.
+
+Than I tried to create a lightful morse code output with the following modules.
+
+=over 3
+
+=item * Term::Size::Perl chars, to determine the width of the terminal
+
+=item * Term::ANSIScreen, for coloured output on the same line.
+
+=item * Text::Morse, alternative presentation of morse code.
+
+=item * Time::HiRes usleep, for sleeping in micro seconds granularity.
+
+=back
+
+
+=begin html
+
+<h2> Download and References </h2>
+<b>Download File:</b><a href="ch-1.pl" download>Solution PWC #35 Task #1 ch-1.pl</a><br>
+<b>Download File:</b><a href="ch-2.pl" download>Solution PWC #35 Task #2 ch-2.pl</a><br>
+<br>
+<a target=_blank href="https://en.wikipedia.org/wiki/Morse_code">https://en.wikipedia.org/wiki/Morse_code</a>
+
+=end html
+
+=head1 SYNOPSIS
+
+ # perldoc ch-1.pl		- POD
+ ./ch-1.pl <command|string> [string]
+ # ./ch-1.pl "My name is? hello123!"
+ # ./ch-1.pl "SOS SOS"
+ # ./ch-1.pl light "SOS SOS"
+ # ./ch-1.pl morse "SOS SOS"
+ # ./ch-1.pl html		- HTML/CSS in ch-1.html/pwc.css
+ # ./ch-1.pl help		- Usage information
+
+
+=head1 Main program
+
+In the main program the used modules are included and the hashes for the binary morse
+transformation are defined. Next the command or test string are read from the argument
+list. I use two standard commands, "help" and "html".
+
+ use strict;
+ use warnings;
+ use Text::Morse;
+ use Term::ANSIScreen qw(:color :cursor :screen);
+ use Term::Size::Perl qw(chars);
+ use Time::HiRes qw(usleep);
+
+ my (%code,%gap);
+ my $cmd = shift @ARGV;		# Read command or text string
+ if(!$cmd) { 
+	print "ch-1.pl (Version 1.0) PWC #35 Task #1: Encode Text to Binary Morse Code\n";
+	usage(); 
+	exit 0; 
+ }
+ elsif($cmd eq "html") { html(); exit 0; }
+ elsif($cmd eq "help") { usage(); exit 0; }
+
+=head2 Solution with module Text::Morse
+
+This is not the required solution, but it exists a module Text::Morse that makes it
+very easy to encode the morse alphabet.
+
+ elsif($cmd eq "morse") {
+	my $m = new Text::Morse;
+	my $encoded = $m->Encode($ARGV[0]);
+	print "$encoded\n";
+ }
+
+The output is a dot-hyphen combination with every word on a new line.
+
+ # ./ch-1.pl morse "SOS SOS SOS"
+ ... --- ... 
+ ... --- ... 
+ ... --- ... 
+
+=head2 Solution with Term::ANSIScreen
+
+With Term::ANSIScreen it is possible to change the colour in the rhythm of the morse
+code, so you create a visible morse message. The sleep time is done with C<Time::HiRes
+usleep()> function, because the sleep in seconds seems too long for the morse dot.
+See more below in the C<multi_line()> and C<morse_light()> functions.
+
+ elsif($cmd eq "light") {
+	init();
+	my $filtered = filter($ARGV[0]);
+	my $encoded  = translate($filtered);
+	multi_line($filtered,$encoded);
+ }
+
+ # ./ch-1.pl light "SOS SOS"
+ Sentence: SOS SOS
+ Sentence: 1010100011101110111000101010000000101010001110111011100010101
+
+
+ SOS
+ 101010001110111011100010101
+
+=head2 Required solution as binary encoded string
+
+This default execution is doing the job: Initialize hash table, 
+filtering not encodable characters and translate the string into binary.
+The functions are explained in more details below.
+
+ else {
+	init();
+	my $filtered = filter($cmd);
+	my $encoded  = translate($filtered);
+	print "$encoded\n";
+ }
+
+The output is the wished binary morse string.
+
+ # ./ch-1.pl "SOS SOS"
+ 1010100011101110111000101010000000101010001110111011100010101
+
+When used with a pipe and xargs to the script for Task #2, then it can be
+converted back to the string.
+
+ ./ch-1.pl "SOS SOS" | xargs ./ch-2.pl
+ SOS SOS
+
+ ./ch-1.pl "sos sos" | xargs ./ch-2.pl
+ SOS SOS
+
+=cut
+
+my (%code,%gap);
+my $cmd = shift @ARGV;		# Read command or text string
+if(!$cmd) { 
+	print "ch-1.pl (Version 1.0) PWC #35 Task #1: Encode Text to Binary Morse Code\n";
+	usage(); 
+	exit 0; 
+}
+elsif($cmd eq "html") { html(); exit 0; }
+elsif($cmd eq "help") { usage(); exit 0; }
+elsif($cmd eq "morse") {
+	my $m = new Text::Morse;
+	my $encoded = $m->Encode($ARGV[0]);
+	print "$encoded\n";
+}
+elsif($cmd eq "light") {
+	init();
+	my $filtered = filter($ARGV[0]);
+	my $encoded  = translate($filtered);
+	multi_line($filtered,$encoded);
+}
+else {
+	init();
+	my $filtered = filter($cmd);
+	my $encoded  = translate($filtered);
+	print "$encoded\n";
+}
+
+# ====================== TASK 1 ==============================
+
+=head1 Definition Task #1: Encode Text to Binary Morse Code
+
+Write a program to encode text into binary encoded morse code.
+
+Pay attention to any changes which might need to be made to the text to make it valid morse code.
+
+Morse code consists of dots, dashes and gaps. It can be encoded in binary in the following fashion:
+dot: 1
+dash: 111
+intra-character gap: 0
+character gap: 000
+word gap: 0000000
+
+An intra-character gap is inserted between the dots and dashes in a character.
+
+=cut
+
+# ====================== TASK 1 ==============================
+
+=head1 Functions
+
+=head2 init()
+
+The init() function initializes the hash table to translate each letter
+into the binary string.
+
+ sub init {
+	%code = (
+		'A' => "10111",
+		'B' => "111010101",
+		'C' => "11101011101",
+		'D' => "1110101",
+		'E' => "1",
+		'F' => "101011101",
+		'G' => "111011101",
+		'H' => "1010101",
+		'I' => "101",
+		'J' => "1011101110111",
+		'K' => "111010111",
+		'L' => "101110101",
+		'M' => "1110111",
+		'N' => "11101",
+		'O' => "11101110111",
+		'P' => "10111011101",
+		'Q' => "1110111010111",
+		'R' => "1011101",
+		'S' => "10101",
+		'T' => "111",
+		'U' => "1010111",
+		'V' => "101010111",
+		'W' => "101110111",
+		'X' => "11101010111",
+		'Y' => "1110101110111",
+		'Z' => "11101110101",
+		'1' => "10111011101110111",
+		'2' => "101011101110111",
+		'3' => "1010101110111",
+		'4' => "10101010111",
+		'5' => "101010101",
+		'6' => "11101010101",
+		'7' => "1110111010101",
+		'8' => "111011101110101",
+		'9' => "11101110111011101",
+		'0' => "1110111011101110111"
+	);
+	%gap = (
+		'cg' => "000",	# character gap
+		'wg' => "0000000"	# word gap
+	);
+ }
+
+=cut
+
+sub init {
+	%code = (
+		'A' => "10111",
+		'B' => "111010101",
+		'C' => "11101011101",
+		'D' => "1110101",
+		'E' => "1",
+		'F' => "101011101",
+		'G' => "111011101",
+		'H' => "1010101",
+		'I' => "101",
+		'J' => "1011101110111",
+		'K' => "111010111",
+		'L' => "101110101",
+		'M' => "1110111",
+		'N' => "11101",
+		'O' => "11101110111",
+		'P' => "10111011101",
+		'Q' => "1110111010111",
+		'R' => "1011101",
+		'S' => "10101",
+		'T' => "111",
+		'U' => "1010111",
+		'V' => "101010111",
+		'W' => "101110111",
+		'X' => "11101010111",
+		'Y' => "1110101110111",
+		'Z' => "11101110101",
+		'1' => "10111011101110111",
+		'2' => "101011101110111",
+		'3' => "1010101110111",
+		'4' => "10101010111",
+		'5' => "101010101",
+		'6' => "11101010101",
+		'7' => "1110111010101",
+		'8' => "111011101110101",
+		'9' => "11101110111011101",
+		'0' => "1110111011101110111"
+	);
+	%gap = (
+		'cg' => "000",	# character gap
+		'wg' => "0000000"	# word gap
+	);
+}
+
+=head2 $filtered = filter($string)
+
+The C<$string> is filtered to characters that can be encoded in morse alphabet and
+returned as C<$filtered> string.
+
+ sub filter {
+	my ($in) = @_;
+	$in =~ tr/a-z/A-Z/;   # Small to Capital letters
+	$in =~ s/\W/ /g;      # Non-Word to Space
+	$in =~ s/ +/ /g;      # 1-or-more spaces make one space
+	$in =~ s/\s*$//;      # Eleminate Spaces at end.
+	return $in;
+}
+
+=cut
+
+sub filter {
+	my ($in) = @_;
+	$in =~ tr/a-z/A-Z/;   # Small to Capital letters
+	$in =~ s/\W/ /g;      # Non-Word to Space
+	$in =~ s/ +/ /g;      # 1-or-more spaces make one space
+	$in =~ s/\s*$//;      # Eleminate Spaces at end.
+	return $in;
+}
+
+=head2 $encoded = translate($filtered)
+
+The C<$filtered> string is encoded in binary morse alphabet and returned as C<$encoded>.
+
+ sub translate {
+	my ($in) = @_;                      # filtered text string
+	my $b;                              # binary result
+	my @chars = split(//,$in);          # array of every character
+	my $type = "";
+	for( my $i=0; $i<=$#chars; $i++ ) { # loop over every char
+		my $e = $chars[$i];
+		my $n = $chars[$i+1];
+		if($e eq " ") { 
+			$b .= $gap{wg};             # if space, word gap
+			next; 
+		}
+		else { 
+			$b .= $code{$e};            # encode char
+		}            
+		if($i<$#chars) {                # gap not for last character
+			if($n ne " ") {             # only if next is not SPACE
+				$b .= $gap{cg};         # character gap
+			}
+		}
+	}
+	return $b;                          # return binary result
+ }
+
+=cut
+
+sub translate {
+	my ($in) = @_;                      # filtered text string
+	my $b;                              # binary result
+	my @chars = split(//,$in);          # array of every character
+	my $type = "";
+	for( my $i=0; $i<=$#chars; $i++ ) { # loop over every char
+		my $e = $chars[$i];
+		my $n = $chars[$i+1];
+		if($e eq " ") { 
+			$b .= $gap{wg};             # if space, word gap
+			next; 
+		}
+		else { 
+			$b .= $code{$e};            # encode char
+		}            
+		if($i<$#chars) {                # gap not for last character
+			if($n ne " ") {             # only if next is not SPACE
+				$b .= $gap{cg};         # character gap
+			}
+		}
+	}
+	return $b;                          # return binary result
+}
+
+=head2 multi_line($txt,$str)
+
+The function C<multi_line()> is printing the Word and Binary representation of the 
+input to a defined position on the screen during the morse code is played. 
+The morse code is played on a defined line to visually show the morsed text.
+
+On line 5 each word is printed as it is morsed.
+
+On line 6 each binary is printed as it is morsed.
+
+On line 7 is the morse light show.
+
+ sub multi_line {
+	my ($txt,$str) = @_;
+	local $| = 1; # This autoflush is really necessary.
+	cls;
+	locate 1,0; print "Words: $txt";  # Print whole Text
+	locate 2,0; print "Bin  : $str";  # Print whole binary
+	locate 5,0; clline;               # Clear line 5
+	locate 6,0; clline;               # Clear line 6
+
+	sleep 1;
+	my @s = split(//,$str);           # Split binary string in each bit.
+	my @t = split(" ",$txt);          # Split text string in each word.
+	my $pos = 1;                      # X-Poxition for output
+	my $c;                            # Binary characters.
+	locate 5,1; print shift @t;
+	for( my $i=0; $i<=$#s; $i++ ) {   # Collect sequence of "0" or "1".
+		$c .= $s[$i];
+		next if defined($s[$i+1]) and $s[$i+1] eq $s[$i];
+
+		my $len = length($c);         # Determine length of sequence.
+		my $on  = substr($c,0,1);     # Determine if "0" or "1"
+		locate 6,$pos; print "$c";    # Print Sequence
+		$pos += $len;                 # Increase position according to length
+		morse_light($on,$len);        # MORSE visual
+
+		if(($on eq "0") and ($len == 7)) { # Clear line at end of each word.
+			locate 5,0; clline; $pos = 1; 
+			locate 6,0; clline; $pos = 1; 
+			locate 5,1; print shift @t;
+		}
+		$c = "";
+	} 	
+ }
+
+=cut
+
+sub multi_line {
+	my ($txt,$str) = @_;
+	local $| = 1; # This autoflush is really necessary.
+	cls;
+	locate 1,0; print "Words: $txt";  # Print whole Text
+	locate 2,0; print "Bin  : $str";  # Print whole binary
+	locate 5,0; clline;               # Clear line 5
+	locate 6,0; clline;               # Clear line 6
+
+	sleep 1;
+	my @s = split(//,$str);           # Split binary string in each bit.
+	my @t = split(" ",$txt);          # Split text string in each word.
+	my $pos = 1;                      # X-Poxition for output
+	my $c;                            # Binary characters.
+	locate 5,1; print shift @t;
+	for( my $i=0; $i<=$#s; $i++ ) {   # Collect sequence of "0" or "1".
+		$c .= $s[$i];
+		next if defined($s[$i+1]) and $s[$i+1] eq $s[$i];
+
+		my $len = length($c);         # Determine length of sequence.
+		my $on  = substr($c,0,1);     # Determine if "0" or "1"
+		locate 6,$pos; print "$c";    # Print Sequence
+		$pos += $len;                 # Increase position according to length
+		morse_light($on,$len);        # MORSE visual
+
+		if(($on eq "0") and ($len == 7)) { # Clear line at end of each word.
+			locate 5,0; clline; $pos = 1; 
+			locate 6,0; clline; $pos = 1; 
+			locate 5,1; print shift @t;
+		}
+		$c = "";
+	} 	
+}
+
+=head2 morse_light($on,$length)
+
+The C<morse_light()> function is doing the visual morse in line 7. First the max width
+of the terminal is determined with C<Term::Size::Perl char()> function. Then the position
+on the terminal is set with C<Term::ANSIScreen locate()> function. The color is changed
+with C<color()> function and Spaces are printed in that new color. An usleep keeps the color
+for the morse time and everything is resetted to original color.
+
+ sub morse_light {
+	my ($on,$length) = @_;   # $on = 0|1, $length is the length for the morse sign.
+	my $max = chars;         # Terminal width
+
+	locate 7,1;              # Set position
+	if($on) { color 'white on red'; clline; } # Set color for ON
+	print " " x $max;        # Print Spaces
+	usleep 200000 * $length; # Sleep length of morse sign.
+
+	print color 'reset';     # Reset color for location and print spaces.
+	locate 7,1;
+	print " " x $max;
+ }
+
+=cut
+
+sub morse_light {
+	my ($on,$length) = @_;   # $on = 0|1, $length is the length for the morse sign.
+	my $max = chars;         # Terminal width
+
+	locate 7,1;              # Set position
+	if($on) { color 'white on red'; clline; } # Set color for ON
+	print " " x $max;        # Print Spaces
+	usleep 200000 * $length; # Sleep length of morse sign.
+
+	print color 'reset';     # Reset color for location and print spaces.
+	locate 7,1;
+	print " " x $max;
+}
+
+# ================================ Usage ============================
+sub usage {
+	print "./ch-1.pl <command|string>\n";
+	print "\n";
+	print "   command, html|help\n";
+	print "      help,  Prints out some usage information.\n";
+	print "      html,  Writes HTML and CSS from POD.\n";
+	print "\n";
+	print "   Examples:\n";
+	print "      # perldoc ch-1.pl\n";
+	print "      # ./ch-1.pl help\n";
+	print "      # ./ch-1.pl html\n";
+}
+
+sub html {
+	# ------------- Create HTML --------------
+	qx[ pod2html --header --title \"Perl Weekly Challenge #35 Task #1, Encode Morse\" --css \"pwc.css\" ch-1.pl > ch-1.html ];
+
+	# ------------- Create CSS --------------
+	my $CSS =<<CSS;
+body { margin-left:auto; margin-right:auto; width:80%; }
+h1   { border-bottom:4px solid red; }
+h2   { border-bottom:2px solid orange; }
+pre  { border:2px solid grey; background-color:#eef; padding:10px; }
+li   { padding:5px; }
+a    { text-decoration:none; color:black; padding:4px; }
+a:hover { background-color: brown; color:white; }
+._podblock_ { width:100%; background-color:black; color:white; padding:10px; }
+CSS
+
+	open(CSS, ">pwc.css") or die "Cant open pwc.css!\n";
+	print CSS $CSS;
+	close CSS;
+}
+
+=head1 AUTHOR
+
+Chuck
+
+=cut
+
+# ############################## END #############################################
+
diff --git a/challenge-035/burkhard-nickels/perl5/ch-2.pl b/challenge-035/burkhard-nickels/perl5/ch-2.pl
new file mode 100755
index 0000000000..f100e1b238
--- /dev/null
+++ b/challenge-035/burkhard-nickels/perl5/ch-2.pl
@@ -0,0 +1,282 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings;
+
+=head1 Perl Weekly Challenge #34 Task #2: Decode Binary Morse Code
+
+This week PWC in Task #2 shall decode binary morse code. In Task #2 it is done
+the same way as in Task #1 only vice versa. A hash table is used to translate
+every binary representation to a letter.
+
+The output of Task #1 can be used as input of Task #2 with the use of Pipe "|"
+and xargs, see below.
+
+=begin html
+
+<h2> Download and References </h2>
+<b>Download File:</b><a href="ch-1.pl" download>Solution PWC #35 Task #1 ch-1.pl</a><br>
+<b>Download File:</b><a href="ch-2.pl" download>Solution PWC #35 Task #2 ch-2.pl</a><br>
+<br>
+<a target=_blank href="https://en.wikipedia.org/wiki/Morse_code">https://en.wikipedia.org/wiki/Morse_code</a>
+
+=end html
+
+=head1 SYNOPSIS
+
+ # perldoc ch-2.pl		- POD
+ ./ch-2.pl <command|string>
+ # ./ch-2.pl html		- HTML/CSS in ch-1.html/pwc.css
+ # ./ch-2.pl help		- Usage information
+
+ # ./ch-1.pl "My name is? hello123!"
+ 11101110001110101110111000000011101000101110001110111000100000001010001010100000001010101000100010111010100010111010100011101110111000101110111011101110001010111011101110001010101110111
+
+ # ./ch-2.pl "11101110001110101110111000000011101000101110001110111000100000001010001010100000001010101000100010111010100010111010100011101110111000101110111011101110001010111011101110001010101110111"
+ MY NAME IS HELLO123
+
+ # ./ch-1.pl "My name is? hello123!" | xargs ./ch-2.pl
+ MY NAME IS HELLO123
+
+=head1 Definition Task #2
+
+Write a program to decode binary morse code.
+
+Consider how it might be possible to recover from badly formed morse code.
+a) by splitting the morse code on gaps
+b) without looking further than one digit ahead
+
+=head1 Main program
+
+The main program defines the hashes to translate from binary morse code to
+text, reads the arguments and does the translation.
+
+ my (%code,%gap);           # Define Hash tables
+ my $cmd = shift @ARGV;		# Read command or text string.
+ if(!$cmd) { 
+	print "ch-2.pl (Version 1.0) PWC #35 Task #2: Decode Binary Morse Code\n";
+	usage(); 
+	exit 0; 
+ }
+ elsif($cmd eq "html") { html(); exit 0; }
+ elsif($cmd eq "help") { usage(); exit 0; }
+ else {
+	init();                           # Initialize hash table.
+	my $decoded  = translate($cmd);   # Decode from binary to text.
+	print "$decoded\n";               # Print decoded string.
+ }
+
+=cut
+
+my (%code,%gap);
+my $cmd = shift @ARGV;		# Read command or text string
+if(!$cmd) { 
+	print "ch-2.pl (Version 1.0) PWC #35 Task #2: Decode Binary Morse Code\n";
+	usage(); 
+	exit 0; 
+}
+elsif($cmd eq "html") { html(); exit 0; }
+elsif($cmd eq "help") { usage(); exit 0; }
+else {
+	init();
+	my $decoded  = translate($cmd);
+	print "$decoded\n";
+}
+
+=head2 init()
+
+The C<init()> function initializes the hash table to translate letters to binary
+morse code and to translate the gaps inbetween.
+
+ sub init {
+	%code = (
+		'10111' => "A",
+		'111010101' => "B",
+		'11101011101' => "C",
+		'1110101' => "D",
+		'1' => "E",
+		'101011101' => "F",
+		'111011101' => "G",
+		'1010101' => "H",
+		'101' => "I",
+		'1011101110111' => "J",
+		'111010111' => "K",
+		'101110101' => "L",
+		'1110111' => "M",
+		'11101' => "N",
+		'11101110111' => "O",
+		'10111011101' => "P",
+		'1110111010111' => "Q",
+		'1011101' => "R",
+		'10101' => "S",
+		'111' => "T",
+		'1010111' => "U",
+		'101010111' => "V",
+		'101110111' => "W",
+		'11101010111' => "X",
+		'1110101110111' => "Y",
+		'11101110101' => "Z",
+		'10111011101110111' => "1",
+		'101011101110111' => "2",
+		'1010101110111' => "3",
+		'10101010111' => "4",
+		'101010101' => "5",
+		'11101010101' => "6",
+		'1110111010101' => "7",
+		'111011101110101' => "8",
+		'11101110111011101' => "9",
+		'1110111011101110111' => "0",
+	);
+	%gap = (
+		'cg' => "000",	# character gap
+		'wg' => "0000000"	# word gap
+	);
+ }
+
+
+=cut
+
+sub init {
+	%code = (
+		'10111' => "A",
+		'111010101' => "B",
+		'11101011101' => "C",
+		'1110101' => "D",
+		'1' => "E",
+		'101011101' => "F",
+		'111011101' => "G",
+		'1010101' => "H",
+		'101' => "I",
+		'1011101110111' => "J",
+		'111010111' => "K",
+		'101110101' => "L",
+		'1110111' => "M",
+		'11101' => "N",
+		'11101110111' => "O",
+		'10111011101' => "P",
+		'1110111010111' => "Q",
+		'1011101' => "R",
+		'10101' => "S",
+		'111' => "T",
+		'1010111' => "U",
+		'101010111' => "V",
+		'101110111' => "W",
+		'11101010111' => "X",
+		'1110101110111' => "Y",
+		'11101110101' => "Z",
+		'10111011101110111' => "1",
+		'101011101110111' => "2",
+		'1010101110111' => "3",
+		'10101010111' => "4",
+		'101010101' => "5",
+		'11101010101' => "6",
+		'1110111010101' => "7",
+		'111011101110101' => "8",
+		'11101110111011101' => "9",
+		'1110111011101110111' => "0",
+	);
+	%gap = (
+		'cg' => "000",	# character gap
+		'wg' => "0000000"	# word gap
+	);
+}
+
+=head2 translate($in)
+
+The C<translate()> function in Task #2 is doing the translation from binary code
+back to text. The whole binary string is first split at word gap "0000000".
+A second split is done for every word at character gap "000". Then the letter
+is searched in a hash table and concatenated to one string.
+
+ sub translate {
+	my ($in) = @_;                           # binary string
+	my @words = split(/$gap{wg}/,$in);       # array of every word
+	my @strings;
+	for( my $i=0; $i<=$#words; $i++ ) {      # loop over every char
+		my @a = split(/$gap{cg}/,$words[$i]);
+		my $s;                               # word
+		foreach my $a (@a) {
+			if(!$code{$a}) { $s .= "ERROR($a)"; } # Letter not found
+			$s .= $code{$a};
+		}
+		push(@strings,$s);
+	}
+	return join(" ",@strings);               # return string result
+ }
+
+The following command shows the output of a proper binary string, followed by
+the output of 2 missing "11" digits for the "O", and followed by 1 missing "1"
+digit, that leads to an error message included in the output string.
+
+ ./ch-2.pl 1010100011101110111000101010000000101010001110111011100010101
+ SOS SOS
+
+ ./ch-2.pl 10101000111010111000101010000000101010001110111011100010101
+ SKS SOS
+
+ ./ch-2.pl 101010001110110111000101010000000101010001110111011100010101
+ S(ERROR 1110110111)S SOS
+
+=cut
+
+sub translate {
+	my ($in) = @_;                           # binary string
+	my @words = split(/$gap{wg}/,$in);       # array of every word
+	my @strings;
+	for( my $i=0; $i<=$#words; $i++ ) {      # loop over every char
+		my @a = split(/$gap{cg}/,$words[$i]);
+		my $s;                               # word
+		foreach my $a (@a) {
+			if(!$code{$a}) { $s .= "(ERROR $a)"; } # Letter not found
+			else { $s .= $code{$a}; }
+		}
+		push(@strings,$s);
+	}
+	return join(" ",@strings);               # return string result
+}
+
+
+# ================================ Usage ============================
+sub usage {
+	print "./ch-2.pl <command|string>\n";
+	print "\n";
+	print "   command, html|help\n";
+	print "      help,  Prints out some usage information.\n";
+	print "      html,  Writes HTML and CSS from POD.\n";
+	print "   string,  The binary string to decode.\n";
+	print "\n";
+	print "   Examples:\n";
+	print "      # perldoc ch-2.pl\n";
+	print "      # ./ch-2.pl help\n";
+	print "      # ./ch-2.pl html\n";
+}
+
+sub html {
+	# ------------- Create HTML --------------
+	qx[ pod2html --header --title \"Perl Weekly Challenge #35 Task #2, Decode binary morse code.\" --css \"pwc.css\" ch-2.pl > ch-2.html ];
+
+	# ------------- Create CSS --------------
+	my $CSS =<<CSS;
+body { margin-left:auto; margin-right:auto; width:80%; }
+h1   { border-bottom:4px solid red; }
+h2   { border-bottom:2px solid orange; }
+pre  { border:2px solid grey; background-color:#eef; padding:10px; }
+li   { padding:5px; }
+a    { text-decoration:none; color:black; padding:4px; }
+a:hover { background-color: brown; color:white; }
+._podblock_ { width:100%; background-color:black; color:white; padding:10px; }
+CSS
+
+	open(CSS, ">pwc.css") or die "Cant open pwc.css!\n";
+	print CSS $CSS;
+	close CSS;
+}
+
+=head1 AUTHOR
+
+Chuck
+
+=cut
+
+# ############################## END #############################################
+