sub mkamatch { # (pattern,kmismatches) use integer; my $p = shift; my $k = shift; my $m = length($p); $k = (10 * $m) / 100 + 1 unless defined $k; my @p2 = map { 1 << $_ } 0 .. 31; my @t = (0) x 256; # alphabet size my $i = -1; $t[$_] |= $p2[++$i] for (unpack("C*",$p)); my (@s,@r); $#s = $#r = $k; for ($r[0] = 0, my $i = 0; $i < $k; $i++){ $r[$i+1] = $r[$i] | $p2[$i]; } sub { my $key = shift; my $n = length($key); my $mb = $p2[$m-1]; my $ret = -1; my @str = unpack("C*",$key); for ($s[0] = 0, my $i = 0; $i < $n; $i++){ $s[0] = (($s[0] << 1) | 1) & (my $tc = $t[$str[$i]]); for (my $j = 1; $j <= $k; $j++){ $s[$j] = (((($r[$j] << 1) & $tc) | (($r[$j-1] | $s[$j-1]) << 1)) | $r[$j-1]) | 1; } $ret = $i > $m ? $i - $m : 0, last if $s[$k] & $mb; @r = @s; } $ret; } }