8<---------------------------------------------------------------------------
#!/usr/bin/perl -w
#
# Exersize 4.12.1 solution.
#
# Raymond Fellers, Ph.D.
# csci44a@yahoo.com
# csci44a Perl I
# Chabot College
#
use strict;

print "Do you want to READ a file or WRITE a file? ";
my $readWrite = <>;
chomp($readWrite);

if($readWrite eq 'READ') {
    print "What is the name of the input file? ";
    my $file = <>;
    chomp($file);
    open(FH,"<$file") or die "Can't open $file : $!\n";
    print "This file contains:\n";
    while(<FH>) { print "$_"; }
    close(FH);
}elsif($readWrite eq 'WRITE'){
    print "What is the name of the output file? ";
    my $file = <>;
    chomp($file);
    open(FH,">$file") or die "Can't create $file : $!\n";
    my @input = ();
    while(1) {
        print "Enter a string. ";
        print "Type QUIT if you are done. ";
        my $input = <>;
        chomp($input);
        last if($input eq 'QUIT');
        print FH "$input\n";
    }
    close(FH);
    print "Finished entering data. ";
    print "Data written to $file.\n";
}else{
    print "You must enter READ or WRITE.";
}
exit;

8<---------------------------------------------------------------------------
#!/usr/bin/perl -w
#
# Exersize 5.9.1 solution.
#
# Raymond Fellers, Ph.D.
# csci44a@yahoo.com
# csci44a Perl I
# Chabot College
#
use strict;

my %blackBook = ("Briteny Spears" => "714-555-4364",
                 "Christina Aguilera" => "453-555-7398",
                 "Jennifer Lopez" => "714-555-6873",
                 "Beyonce Knowles" => "312-555-3901",
                 "Juhi Chawla" => "682-555-2975"
                 );

print "It's Friday night.  Who are you going to call? ";
my $name = <>;
chomp($name);

if(exists $blackBook{$name}) {
    print "$name\'s phone number is $blackBook{$name}. Good luck!\n";
}else{
    print "You don't know $name.\n";
}

exit;