^([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])\.
([01]?\d\d?|2[0-4]\d|25[0-5])\.([01]?\d\d?|2[0-4]\d|25[0-5])

##</code><code>##

sub validip {
  my ($ip)=@_;
  my $x;
  foreach ($ip=~/^(\d+)\.(\d+)\.(\d+)\.(\d+)$/){
    $x++ if(($_>=0)&&($_<=255));
  }
  return($x==4);
}