I-Studio Blog

Imagine that you need to delete words that contain duplicate letters.

The first choice:

my $a = "1asdf 2sdfg 3dfggdf 4sdfrrsdf 5sdfsdf 6dghgyyghf 7fdfgd 8hgggiu";
my @b = split / /, $a;
foreach my $w (@b) {
    next if $w =~ /(.)\1/;
    print $w." ";
}

But we can do it more simple:

$a =~ s/(\b.*?\b)\s(\w+(.)\3\w+)/$1/g;

Example:

$ perl -e 'my $a = "1asdf 2sdfg 3dfggdf 4sdfrrsdf 5sdfsdf 6dghgyyghf 7fdfgd 8hgggiu"; $a =~ s/(\b.*?\b)\s(\w+(.)\3\w+)/$1/g; warn $a'
1asdf 2sdfg 5sdfsdf 7fdfgd at -e line 1.