| 摘要 |
PURPOSE:To perform fast retrieval by using a memory device small in capacity by encoding a standardized character string by appearance frequency, and storing by segmenting the bit pattern of a code as try structure. CONSTITUTION:A standardizing device 2 standardizes a keyword, and an encoder 6 performs the Huffman encoding of the keyword by the appearance frequency of a partial character string. A try structure part compression device 7 stores by compressing a code string compressed by the encoder 6 to the try structure, and a sequential access non-structural part compression device 8 stores by compressing the remainder of the keyword to a sequential access non-structural part. Furthermore, a retriever 13 performs the Huffman encoding of the standardized character string 11 by using a code table 12 for Huffman code, and retrieves a corresponding keyword character string from a dictionary 9 for retrieval. In such a case, the try structure of list format is stored by compressing by segmenting (n) bits (n>=1) from the forefront of an obtained code and using it in the index of the try structure. |
