##########################
# Original wc.pl from hw1
##########################

use strict;
my $line;
my $total = 0;
while ($line = <>) {
  chomp($line);
  my @words = split(' ', $line);
  $total += $#words + 1;
}
print "$total\n";

##########################
# wc1.pl
# opens a fixed filename
##########################

use strict;

my $line;
my $total = 0;

my $filename = "hw1.txt";
my $fh;

my $status = open($fh, $filename);
if (!$status) { die "could not open $filename\n"; }

while ($line = <$fh>) {
  chomp($line);
  my @words = split(' ', $line);
  $total += $#words + 1;
}

close($fh);
print "$total\n";

##########################
# wc1-bad.pl
# opens a fixed filename 
# that does not exist
##########################

use strict;

my $line;
my $total = 0;

my $filename = "hw1-missing.txt";
my $fh;

my $status = open($fh, $filename);
if (!$status) { die "could not open $filename\n"; }

while ($line = <$fh>) {
  chomp($line);
  my @words = split(' ', $line);
  $total += $#words + 1;
}

close($fh);
print "$total\n";

##########################
# wc2.pl
# takes filename from @ARGV
##########################

use strict;

my $line;
my $total = 0;

my $filename = '';
my $fh;

$filename = shift(@ARGV);
if ($filename eq '') { die "no filename provided\n"; }

my $status = open($fh, $filename);
if (!$status) { die "could not open $filename\n"; }

while ($line = <$fh>) {
  chomp($line);
  my @words = split(' ', $line);
  $total += $#words + 1;
}

close($fh);
print "$total\n";

##########################
# wc3.pl
# takes filename from @ARGV
# but if no files provided then
# filehandle is set to standard input
##########################

use strict;

my $line;
my $total = 0;

my $filename = '';
my $fh;

$filename = shift(@ARGV);

if ($filename eq '') { 
    $fh = *STDIN; 
} else {
    my $status = open($fh, $filename);
    if (!$status) { die "could not open $filename\n"; }
}

while ($line = <$fh>) {
  chomp($line);
  my @words = split(' ', $line);
  $total += $#words + 1;
}

close($fh);
print "$total\n";

##########################
# wc4.pl
# does the same thing as wc3.pl
# except uses the default behaviour
# of the readline (<>) operator
##########################

use strict;

my $line;
my $total = 0;

while ($line = <>) {
  chomp($line);
  my @words = split(' ', $line);
  $total += $#words + 1;
}

print "$total\n";

##########################
# wc5.pl
# same as wc4.pl but also
# uses default variable $_
# which takes value returned
# by the readline function (<>)
##########################

use strict;

my $total = 0;

while (<>) {
  chomp($_);
  my @words = split(' ', $_);
  $total += $#words + 1;
}

print "$total\n";

##########################
# wc6.pl
# same as wc5.pl but also uses
# the default behaviour of
# the perl functions used in
# the while loop, e.g. chomp
# without any arguments is
# taken by perl to be chomp($_)
##########################

use strict;

my $total = 0;

while (<>) {
  chomp;
  my @words = split;
  $total += $#words + 1;
}

print "$total\n";

##########################
# wc7.pl
# uses default return location
# for split as well which is @_
##########################

use strict;

my $total = 0;

while (<>) {
  chomp;
  split;
  $total += $#_ + 1;
}

print "$total\n";


############################