15. A pattern recognition device comprising: data input means for receiving various inputted recognition data comprising a plurality of consecutive recognition elements; data storing means for storing a plurality of items of standard data each made up of a plurality of consecutive standard elements, said plurality of items of standard data having a predetermined correspondence to prescribed recognition data; element storing means for storing a predetermined tree structure of data, said tree structure having a root node and a plurality of subordinate nodes, each said subordinate node corresponding to one of said standard elements; said plurality of subordinate nodes being linked by a number of parent nodes, said number of parent nodes being smaller than a number of said subordinate nodes, said parent nodes each corresponding, on average, to a plurality of mutually similar ones of said standard elements; data dividing means for generating said plurality of consecutive recognition elements from said inputted recognition data; parent distance calculating means for calculating respective parent node distances of similarity for each of said recognition elements; parent node selecting means for selecting ones of said parent nodes based on a magnitude of said respective parent node distances of similarity; subordinate distance calculating means for calculating respective subordinate node distances of similarity for each of said recognition elements only for ones of said subordinate nodes linked to said selected parent nodes; distance storing means for storing only once, in order, at predetermined positions, said respective parent node distances of similarity, and for storing, in order, at other predetermined positions, only said respective subordinate node distances of similarity for said subordinate nodes of said selected parent nodes; identifier storing means for storing, for each of said parent nodes, for each of said recognition elements, an identifier indicating the presence or absence of subordinate node distances; position storing means for storing, as position data, the storage positions of said subordinate node distances in said distance storing means for each said identifier indicating said presence of said subordinate node distances; distance reading means for reading said identifiers from said identifier storing means according to identification data of said parent nodes and for reading said subordinate node distances from said distance storing means corresponding to said position data when one of said identifiers indicates that said subordinate node distances are present, and for reading said parent node distances from said predetermined positions when one of said identifiers indicates that said subordinate node distances are not present; distance accumulating means for calculating respective standard data item distances for consecutive ones of said recognition elements, based on distances read by said distance reading means; and result outputting means for selectively outputting standard data, for which said distances accumulated by said distance accumulating means are smallest, as the recognition result.
16. A pattern recognition device according to claim 15 wherein said recognition data inputted to said data input means are made up of speech signals and standard data catalogued in said data storing means are made up of words.