SEARCH DEVICE, SEARCH METHOD, AND SEARCH PROGRAM

摘要

The present invention speeds up a search when the search is performed by limiting the search range on a search tree to a search condition that produces a prefix match with the previous search condition. A search tree storage unit (210) stores a search tree representing a plurality of search targets, which are element strings. A previous-search condition storage unit (240) stores a previous-search element string. A previous-search path storage unit (250) stores previous-search path information indicating a hierarchical node corresponding to a target sequence from among the nodes traced when searching the previous-search element string in the search tree. A search-start node determination unit (110) collectively compares an element string prior to the target sequence to an inputted search element string and the previous-search element string, and when there is a match, decides on the node indicated by the previous-search path information as the search-start node. A search unit (120) performs a search beginning at the search-start node on the search tree for an element subsequent to the target sequence of the inputted search element string.