| 摘要 |
<p>PROBLEM TO BE SOLVED: To apply ID of a fixed length, in which the length of an input key of variable length is restricted.SOLUTION: Based on a plurality of keys formed from an input byte string of variable length, a node addition part 34 constructs a trie structure representing a plurality of keys by combining bytes of prefix portions having a common key. A flag application part 36 forms a bit array for each of nodes of the trie structure, the bit arrangement being provided with a bit value indicating whether the node is a node holding information about the byte of a key terminal or not. A non-negative integer value ID application part 38 calculates the non-negative integer value of fixed length by a minimal complete hash function having, as input, the relative index value of a bit value in a bit arrangement, for each of bit values indicating a node holding the information about the byte at the key terminal, in a bit arrangement. The non-negative integer value ID application part 38 then applies ID to the key whose node holds information about the byte at the terminal.</p> |
