print ("Enter the number to check if it is actually a number:");
$input = <STDIN>;
while ($input ne "")
{
chop ($input);
if ($input =~ /^\d+$/ | $input =~ /^\d+.\d+$/ | $input =~ /^-\d+$/ | $input =~ /^-\d+.\d+$/)
{
print ("Yes, it is a number\n");
}
else 
{
print ("No, it is not a number\n");
}
print ("Give another input:");
$input = <STDIN>;
}