#!perl use strict; use warnings; my @testdata = (['CCCATCTGTCCTTATTTGCTG', [qw(ATCTG ATTTG)]] ,['ACCCATCTGTCCTTGGCCAT', [qw(CCATC)]] ,['CCACCAGCACCTGTC', [qw(CCACC CCAGC GCACC)]] ,['CCCAACACCTGCTGCCT', [qw(CCAAC ACACC)]]); for (@testdata) { my ($str, $pats) = @$_; print put_bracket($str, @$pats), "\n"; } sub put_bracket { my $str = shift; # Combine multiple match strings into alternations my $rx = join '|', @_; my @brackets; # Store bracket points for every match while ($str =~ /(?=($rx))/g) { push(@brackets, [$-[0], length($1)+$-[0]]); } # Condense overlapping brackets for my $i (0..$#brackets-1) { if ($brackets[$i][1] >= $brackets[$i+1][0]) { $brackets[$i+1][0] = $brackets[$i][0]; @{$brackets[$i]} = (); } } # Apply the brackets (from back to front) while (@brackets) { my $b = pop @brackets; next unless @$b; substr($str, $b->[1], 0) = ']'; substr($str, $b->[0], 0) = '['; } return $str; }