| 摘要 |
<p>The present invention is made of a coupled node tree with a root node (101, 210a) and a node pair (111, 201b, 201c) stored in adjacent areas that is formed by a branch node (112, 211c) and a leaf node (113, 210c), branch nodes, or leaf nodes; the branch node (112, 211c) including a discrimination bit position (115, 231c) in the search key and information indicating a position of one node of a node pair of a link target (116, 221c); the leaf node (113, 210c) including an index key (118, 250c) formed by a bit string that is the target to be searched for; and the coupled node tree is stored in an array (100, 309), the position information for which being the array element number for the array element in which the node related to that position information is stored; wherein any node in the coupled node tree can be used as the start node for a search and by linking from only the smaller of the array element numbers for the node pair, when a leaf node is reached, the search start node can be taken as the root node for any desired subtree requesting a minimum index key value.</p> |
