anchor.diff:  
   -define(Check_sum_fun(X), erlang:crc32(integer_to_list(X))). %hash function for checksum building
   
  --type key()     :: integer().
   -type value()   :: integer().
   -type cell()    :: {Count       :: non_neg_integer(),
  -                    KeySum      :: key(),
  +                    KeySum      :: integer(),
                       KeyHashSum  :: integer(),   %sum c(x) of all inserted keys x, for c = any hashfunction not in hfs
                       ValSum      :: value(),
                       ValHashSum  :: integer()}.  %sum c(y) of all inserted values y, for c = any hashfunction not in hfs
  
positive.code: 
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  -spec is_element(iblt(), key()) -> boolean().
  is_element(#iblt{ hfs = Hfs, table = T, col_size = ColSize }, Key) ->
      Found = lists:foldl(
                fun({ColNr, Col}, Count) ->
  
negative.code: 
  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  
  -spec get(iblt(), ?RT:key()) -> value() | not_found.
  get(#iblt{ table = T, hfs = Hfs, col_size = ColSize }, Key) ->
      p_get(T, Hfs, ColSize, Key).
  
  -spec p_get(table(), ?REP_HFS:hfs(), non_neg_integer(), ?RT:key()) -> value() | not_found.
  p_get([], _, _, _) -> not_found;
  p_get([{ColNr, Col} | T], Hfs, ColSize, Key) ->
      Cell = lists:nth((?REP_HFS:apply_val(Hfs, ColNr, Key) rem ColSize) + 1, Col),
  