Use move-ahead-k to encode each of the strings abcddcbamnopponm and abcdmnopabcdmnop twice, with k = 1 and k = 2. Wait-c-and-move. An element of A is moved to the front only after it has been matched c times to symbols from the input stream (not necessarily c consecutive times). Each element of A should have a counter associated with it, to count the number of matches. This method makes sense in implementations where moving and rearranging elements of A is slow.