morse_code.pl

# date: 10/12/2013
#!/usr/bin/perl
use strict;
use warnings;
my %code = (
    ".-"    => "A",
    "-..."  => "B",
    "-.-."  => "C",
    "-.."   => "D",
    "."     => "E",
    "..-."  => "F",
    "--."   => "G",
    "...."  => "H",
    ".."    => "I",
    ".---"  => "J",
    "-.-"   => "K",
    ".-.."  => "L",
    "--"    => "M",
    "-."    => "N",
    "---"   => "O",
    ".--."  => "P",
    "--.-"  => "Q",
    ".-."   => "R",
    "..."   => "S",
    "-"     => "T",
    "..-"   => "U",
    "...-"  => "V",
    ".--"   => "W",
    "-..-"  => "X",
    "-.--"  => "Y",
    "--.."  => "Z",
    "-----" => "0",
    ".----" => "1",
    "..---" => "2",
    "...--" => "3",
    "....-" => "4",
    "....." => "5",
    "-...." => "6",
    "--..." => "7",
    "---.." => "8",
    "----." => "9");

open(my $input, "<", $ARGV[0]) or die $!;
foreach(<$input>){
    chomp;
    my @words = split("  ", $_);
    for(my $i = 0; $i <= $#words; $i++){
        my @chars = split(" ", $words[$i]);
        for(my $j = 0; $j <= $#chars; $j++){
            $chars[$j] = $code{$chars[$j]};
        }
        $words[$i] = join "", @chars;
    }
    print join " ", @words;
    print "\n";
}
close($input);