#!/usr/bin/perl

while ($line = <>) {
   convertToDb($line);
}

exit(1);

sub convertToDb {
   my ($line) = @_;
   @data = split(/\s+/, $line);
   foreach $item (@data) {
      if ($item == 0) { 
         print "-inf";
      } else {
         $value = 10.0 * log($item/100)/log(10);
         $value = int($value * 1000) / 1000.0;
         print $value;
      }
      print " ";
   }
   print "\n";
}