fooabc123 fooabc321 foobca232 Rate Tilly revdiablo CombatSqu BrowserUk Tilly 89.6/s -- -45% -85% -85% revdiablo 163/s 81% -- -72% -72% CombatSqu 581/s 549% 257% -- -1% BrowserUk 587/s 554% 261% 1% -- abcfoo123 bcafoo321 foo123abc Rate Tilly revdiablo CombatSqu BrowserUk Tilly 91.7/s -- -37% -82% -84% revdiablo 145/s 58% -- -72% -74% CombatSqu 514/s 460% 255% -- -9% BrowserUk 563/s 514% 289% 10% -- foo bor boz bzo Rate Tilly revdiablo BrowserUk CombatSqu Tilly 408/s -- -43% -59% -82% revdiablo 719/s 76% -- -28% -68% BrowserUk 995/s 144% 38% -- -56% CombatSqu 2236/s 449% 211% 125% -- The quick brown fox jump over the lazy dog The quick brown fox jumps over the lazy jumps over the lazy dog The quick brown fox quick brown fox jumps over the lazy dog Rate Tilly revdiablo CombatSqu BrowserUk Tilly 3.59/s -- -59% -89% -95% revdiablo 8.75/s 143% -- -74% -87% CombatSqu 33.4/s 829% 282% -- -51% BrowserUk 68.6/s 1807% 683% 105% -- The quick brown fox jump over the lazy dog The quick brown fox jumps over the lazy jumps over the lazy dog The quick brown fox quick brown fox jumps over the lazy dog x Rate revdiablo CombatSqu BrowserUk Tilly revdiablo 3.79/s -- -71% -91% -95% CombatSqu 12.9/s 240% -- -69% -85% BrowserUk 41.0/s 984% 219% -- -51% Tilly 83.2/s 2098% 546% 103% -- The quick brown fox jump over the lazy dog xThe quick brown fox jump over the lazy dog xxThe quick brown fox jump over the lazy dog xxxThe quick brown fox jump over the lazy dog xxxxThe quick brown fox jump over the lazy dog Rate Tilly BrowserUk revdiablo CombatSqu Tilly 0.761/s -- -98% -100% -100% BrowserUk 44.2/s 5714% -- -99% -99% revdiablo 4728/s 621405% 10589% -- -25% CombatSqu 6305/s 828641% 14153% 33% -- #### #! perl -slw use strict; use Benchmark qw[ cmpthese ]; sub findlcs { my $substr = $_[0]; my $len = length $_[0]; my $off = 0; while ($substr) { my @matches = grep /\Q$substr/, @_; last if @matches == @_; $off++; $len-- and $off=0 if $off+$len > length $_[0]; $substr = substr $_[0], $off, $len; } return $substr; } sub LCSIndex { my $substr = $_[0]; my $len = length $_[0]; my $off = 0; while ($substr) { my @matches = grep { -1 != index $_, $substr } @_; last if @matches == @_; $off++; $len-- and $off=0 if $off+$len > length $_[0]; $substr = substr $_[0], $off, $len; } return $substr; } sub find_lcs { my @index_info; foreach (@_) { my $string = $_; push @index_info, [ \$string, [ 0..length($string) ], ]; } my ($length, @pos) = _find_lcs(0, @index_info); return $length ? substr(${$index_info[0]->[0]}, $pos[0], $length) : undef; } sub _find_lcs { my ($offset, @index_info) = @_; my $last_chars; foreach my $data (@index_info) { my %chars; foreach my $pos (@{$data->[1]}) { my $char = substr(${$data->[0]}, $pos + $offset, 1); next unless length($char); next if $last_chars and not exists $last_chars->{$char}; push @{$chars{$char}}, $pos; } return 0 unless %chars; $last_chars = $data->[2] = \%chars; } my $best_length = 0; my @best_pos; foreach my $char (keys %$last_chars) { my @index_info_for_char = map { [ $_->[0], $_->[2]->{$char} ] } @index_info; my ($length, @pos) = _find_lcs($offset + 1, @index_info_for_char); next if $length < $best_length; $best_length = $length + 1; if (0 == $length++) { @best_pos = map {$_->[1]->[0]} @index_info_for_char; } else { @best_pos = @pos; } } return $best_length, @best_pos; } sub lcs{ my $strings = join "\0", @_; study $strings; my $re = '.*?\0.*?\1' x ( @_ - 1 ); my $lcs; for ( 1 .. length $strings ) { last unless $strings =~ "(.{$_})$re"; $lcs = $1 } return $lcs; } our @arrays = ( [ qw(fooabc123 fooabc321 foobca232) ], [ qw(abcfoo123 bcafoo321 foo123abc) ], [ qw(foo bor boz bzo) ], [ 'The quick brown fox jump over the lazy dog', 'The quick brown fox jumps over the lazy', 'jumps over the lazy dog The quick brown fox', 'quick brown fox jumps over the lazy dog', ], [ 'The quick brown fox jump over the lazy dog', 'The quick brown fox jumps over the lazy', 'jumps over the lazy dog The quick brown fox', 'quick brown fox jumps over the lazy dog', 'x', ], [ 'The quick brown fox jump over the lazy dog', 'xThe quick brown fox jump over the lazy dog', 'xxThe quick brown fox jump over the lazy dog', 'xxxThe quick brown fox jump over the lazy dog', 'xxxxThe quick brown fox jump over the lazy dog', ], ); for ( @arrays ) { print "R: => ", findlcs @$_; print "C: => ", LCSIndex @$_; print "B: => ", lcs @$_; print "T: => ", find_lcs @$_; } for our $array ( @arrays ) { print for $/, @$array; cmpthese( -5, { revdiablo => q[ my $lcs = findlcs @$array ], CombatSqu => q[ my $lcs = LCSIndex @$array ], BrowserUk => q[ my $lcs = lcs @$array ], Tilly => q[ my $lcs = find_lcs @$array ], }); } __END__ P:\test>junk2 R: => foo C: => foo B: => foo T: => foo R: => foo C: => foo B: => foo T: => foo R: => o C: => o B: => o T: => o R: => quick brown fox C: => quick brown fox B: => quick brown fox T: => quick brown fox R: => x C: => x B: => x T: => x R: => The quick brown fox jump over the lazy dog C: => The quick brown fox jump over the lazy dog B: => The quick brown fox jump over the lazy dog T: => The quick brown fox jump over the lazy dog fooabc123 fooabc321 foobca232 Rate Tilly revdiablo CombatSqu BrowserUk Tilly 89.6/s -- -45% -85% -85% revdiablo 163/s 81% -- -72% -72% CombatSqu 581/s 549% 257% -- -1% BrowserUk 587/s 554% 261% 1% -- abcfoo123 bcafoo321 foo123abc Rate Tilly revdiablo CombatSqu BrowserUk Tilly 91.7/s -- -37% -82% -84% revdiablo 145/s 58% -- -72% -74% CombatSqu 514/s 460% 255% -- -9% BrowserUk 563/s 514% 289% 10% -- foo bor boz bzo Rate Tilly revdiablo BrowserUk CombatSqu Tilly 408/s -- -43% -59% -82% revdiablo 719/s 76% -- -28% -68% BrowserUk 995/s 144% 38% -- -56% CombatSqu 2236/s 449% 211% 125% -- The quick brown fox jump over the lazy dog The quick brown fox jumps over the lazy jumps over the lazy dog The quick brown fox quick brown fox jumps over the lazy dog Rate Tilly revdiablo CombatSqu BrowserUk Tilly 3.59/s -- -59% -89% -95% revdiablo 8.75/s 143% -- -74% -87% CombatSqu 33.4/s 829% 282% -- -51% BrowserUk 68.6/s 1807% 683% 105% -- The quick brown fox jump over the lazy dog The quick brown fox jumps over the lazy jumps over the lazy dog The quick brown fox quick brown fox jumps over the lazy dog x Rate revdiablo CombatSqu BrowserUk Tilly revdiablo 3.79/s -- -71% -91% -95% CombatSqu 12.9/s 240% -- -69% -85% BrowserUk 41.0/s 984% 219% -- -51% Tilly 83.2/s 2098% 546% 103% -- The quick brown fox jump over the lazy dog xThe quick brown fox jump over the lazy dog xxThe quick brown fox jump over the lazy dog xxxThe quick brown fox jump over the lazy dog xxxxThe quick brown fox jump over the lazy dog Rate Tilly BrowserUk revdiablo CombatSqu Tilly 0.761/s -- -98% -100% -100% BrowserUk 44.2/s 5714% -- -99% -99% revdiablo 4728/s 621405% 10589% -- -25% CombatSqu 6305/s 828641% 14153% 33% --