#!/usr/bin/perl

use Term::ANSIColor;

sub multiply{
  my $a=shift;
  my $b=shift;
  my $c=($a*$b);
  return ($c);
}

sub valid_number {
       my $input="@_";
       print "You input $input\n";
       unless ( $input =~ m{
			   ^	      #starts with
			   \+?        #0 or 1 plus signs
                           \d	      #a digit
                           \.?        #0 or 1 decimal points
                           \d*        #0 or more digits
                           $          #end of line
                           }xig
              ){
                die "Error: $input is not number.\n";
        }
        return ($input);

}

print color("green"), "Please enter a number:\t",color("reset");
chomp(my $input=<STDIN>);
my $a= &valid_number($input);

print color("green"), "Please enter a second number:\t",color("reset");
chomp(my $input=<STDIN>);
my $b= &valid_number($input);

my $c= &multiply($a,$b);
print color("magenta"),"$a times $b equals $c\n",color("reset");