thank you a lot for this idea.. it didnt work properly with Normalize module so i tried it this way... sorry for taking out strict :)

$times = time;
$filei = "cetnosti";
$filer = "input";
$filew = "output";
$filec = "correct";

open( INFO, $filei ) or die "cetnosti: $!";
$lineno = 1;
while ((defined ($_ = <INFO>)) && ($lineno < 500000)) {
        ( $word, $freq ) = split;
        $ascii_word = $word;
        $ascii_word =~ tr/&#318;&#353;&#269;&#357;&#382;ýáíéäú&#328;ô&
+#283;&#345;&#341;&#314;&#367;ó&#271;&#317;&#352;&#268;&#356;&#381;ÝÁÍ
+ÉÄÚ&#327;Ô&#282;&#344;&#340;&#313;&#366;Ó&#270;/lsctzyaieaunoerrluodL
+SCTZYAIEAUNOERRLUOD/;
        $lineno++;
        if ( exists( $respell{$ascii_word} )) {
            next;
            }
        $respell{$ascii_word} = $word;
        }
close INFO;

open( INPUT, $filer ) or die "input: $!";
open( OUTPUT, "> $filew" ) or die "respelled: $!";

while (<INPUT>) {
        $outstr = '';

        for $tkn ( split /([\s\p{P}]+)/ ) {

                if ( exists( $respell{$tkn} )) {
                $tkn = $respell{$tkn};

                }
        $outstr .= $tkn;
        }
        print OUTPUT $outstr;
        }
close INPUT;
close OUTPUT;
$timee = time;
$timer = $timee - $times;
print "execution time: $timer seconds\n";
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im sure there are many beginners mistakes but it works :) now i would need to compare "output" with "correct". "correct" is a file with diacritic and i need to know how many words were replaced good. is there some way to do this in perl? thank you