 When the maximum code value is reached, encoding proceeds using the existing table, but new codes are not generated for addition to the table.Further refinements include reserving a code to indicate that the code table should be cleared and restored to its initial state (a "clear code", typically the first value immediately after the values for the individual alphabet characters), and a code to indicate the end of data (a "stop code", typically one greater than the clear code).The clear code lets the table be reinitialized after it fills up, which lets the encoding adapt to changing patterns in the input data.