my $substring = 'xxx';
    my $parent = 'xxx xxx xxx';
    my @count = split($substring,$parent);
    my $total = scalar @count;
    print "there are $total $substring in $parent\n"; 
    if( $total == 1 )    { print "None\n"; }
    elsif( $total == 2 ) { print "Unique\n" }
    else                 { print "Duplicates\n"; }