#!/usr/bin/perl
use strict;
use warnings;

print "loops until 4 floats are entered\n";
for (1..4)
{
   my $float = get_float();
   print "$float Ok!!\n"
}   


sub get_float
{
   my $float;
   while ( (print"enter a float \(decimal required\): "), 
            $float = <STDIN>, 
            $float !~ /^\s*(\-|\+)?\d+\.\d*\s*$/)
   {
      print "Input not an float...try again\n";
   }
   $float =~ s/^\s*|\s*$//g; #delete leading/trailing spaces
   return $float;
}

__END__
perl getfloat.pl
loops until 4 floats are entered
enter a float (decimal required):   4.5.3
Input not an float...try again
enter a float (decimal required):         +4,5
Input not an float...try again
enter a float (decimal required):         +4.5
+4.5 Ok!!
enter a float (decimal required):   3
Input not an float...try again
enter a float (decimal required):   3.0
3.0 Ok!!
enter a float (decimal required):   -2.56
-2.56 Ok!!
enter a float (decimal required): +3
Input not an float...try again
enter a float (decimal required): 3.12345
3.12345 Ok!!

##</code><code>##

$float =~ s/^\s*|\s*$//g; #delete leading/trailing spaces
return $float;

##</code><code>##

$float +=0;  #causes creation of numeric value for $float!
return $float;

##</code><code>##

#!/usr/bin/perl
use strict;
use warnings;

#The homework question just defines @colors and @drop 
#and says to remove the things in drop from colors, that's it. 

my @colors = qw(red green blue yellow pink purple brown);
my @drop = qw(pink brown);

my %drop = map{$_ =>1}@drop;
@colors = grep{!$drop{$_}}@colors;

print "@colors \n";  #red green blue yellow purple 

##</code><code>##

#!/usr/bin/perl
use strict;
use warnings;

#The homework question just defines @colors and @drop 
#and says to remove the things in drop from colors, that's it. 

my @colors = qw(red green blue yellow pink purple brown);
my @drop = qw(pink brown);

my %drop;
foreach my $drop (@drop)
{
   $drop{$drop} = 1;  ## WILD!  Hash and scalar drop
                      ## have separate name spaces!
                      ## I would name different, but
                      ## just a namespace demo...
}

my @result;
foreach my $color (@colors)
{
   push @result, $color unless $drop{$color};
}

@colors = @result;

print "@colors \n";  #red green blue yellow purple