JPH0381830A - Device for searching name table - Google Patents

Abstract

PURPOSE:To prevent the efficiency of search from being dropped even when the number of labels is increased by providing the searching device with a means for extracting the chain of labels from a definition work file and registering the extracted chain in a name table by B* tree structure and a name table searching means. CONSTITUTION:The name table label registering means 1-2 extracts the chain of labler in the name table 1-3 having the same hash value from the definition work file 1-1 and registers the extracted chain in the name to table 1-3 by the B* tree structure. The name table searching means 1-5 extracts labels from a reference work file 1-4, calculates hash values and searches the labels chained by the B* tree structure from a hash table. Namely the labels registered in the table 1-3 are stored in the file 1-1 in the random order, the means 1-2 extracts the labels one by one from the file 1-1 and registers respective labels in the table 1-3 as the B* tree structure. Even when the number of labels is increased, the time required for search can be shortened and the memory effi ciency of the table 1-3 can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is used for managing name tables in language processing systems. The present invention relates to searching name tables.

〔overview〕

The present invention is a name table search device that registers and searches name marks in a name table using a chain hash method. By searching for landmarks that are linked in a structure, the time required for searching can be shortened and search efficiency can be increased even when the number of landmarks is large.

[Conventional technology]

Conventionally, this type of name table search uses a chain hash method that uses a hash function uniquely determined from the name being searched to chain names with the same hash value from a hash table of finite size. It was getting worse.

[Problem that the invention seeks to solve]

In the conventional chain hash method described above, even if an ideal hash function is used, if the width of the hash value is n1 and the number of components of the name table is m, the time required for searching is on the order of
(m/m), so there is a drawback that the search efficiency decreases significantly as the number of landmarks increases.

The present invention aims to eliminate such drawbacks and to provide a device that does not reduce search efficiency even when the number of landmarks increases.

[Means for solving problems]

The present invention provides a name table search device that includes a name table having a hash table and registers names in the name table and searches for names using a chain hash method. A name table name registering means extracts the chain from the definition work file and registers it in the name table in a B0 tree structure, and extracts the name from the reference work file, calculates a hash value, and registers the name from the hash table in an 80 tree structure. The present invention is characterized in that it includes a name table search means for searching for chained names.

[Effect]

The name table name registration means extracts names one by one from the definition work file and registers them in the name table as a B* tree structure, and the name table search means extracts the names from the reference work file and calculates its hash value. Search for names that are chained in the B0 tree structure on the hash table.

As a result, even if the number of name tags becomes large, the time required for searching can be shortened, and a name table with high memory efficiency can be created.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

The embodiment of the present invention has a name table search device that includes a name table 1-3 having a hash table 2-1 and uses the chain hash method to register and search name marks in the name table 1-3. Work file 1- defines a chain of names in name table 1-3 with a hash value of
A name table name registration means 1-2 extracts names from reference work file 1-4 and registers them in name table 1-3 in a B* tree structure, and extracts names from reference work file 1-4, calculates hash values, and registers them in hash table 2. -Name table search means 1 for searching for names chained in a B0 tree structure from 1-
5.

Name tags registered in the name table 1-3 are stored in the definition work file 1-1 in random order.

The name table name registration means 1-2 extracts names one by one from the definition work file 1-1 and registers them in the name table 1-3 as a B* tree structure.

Figure 2 shows an example of the format of the name table 1-3 according to the embodiment of the present invention. , and NULL if no component storing a name is chained in the origin pointer array for chaining from the entry corresponding to this nl.
has the value of

Each component of name table 1-3 is one en of the component from hash table 2-1)! They are chained in the J2-2 format, with the pointer to the left of each name pointing to a component with a name smaller or equal to that name, and the pointer to the right pointing to a component with a larger name. Points to an element. If there is nothing to point to, it takes a NULL value.

Name table ABC<BCD<BC in this format
E<BCG<BDE<CDE<DEF<EAB<EFG
An example in which <FGH<FGJ is chained is shown in 2-3 in Figure 2.
~2-10. However, assume that these names have the same hash value using a certain hash function. In FIG. 2, the Δ mark indicates that no value is included.

When the name table name registration means 1-2 reads the name name from the definition work file 1-1, it repeats the process of registering it in the name table in the B* tree structure by the process shown in FIG.

The name table search means 1-5 searches for the name table constructed as described above from the reference work file 1-4 as shown in FIG. That is, the name table search means 1-5 extracts the name mark from the reference work file 1-4, calculates its hash value, and searches the name table from the chain start point on the hash table 2-1.

At this time, if the pointer value is NULL, it is determined as an undefined error.

The name table 1-3 is searched by searching the B0 tree based on the hash value and its name. If the name is found, an overloaded definition check is performed, and if it is not found, an undefined error is determined. In the overloaded definition check process, it is further searched to see if there are names with the same size, and if any, an overloaded definition error is detected. If not, it is assumed that the name mark has been found correctly and the processing for that name mark is executed. In Figure 4, HT (n'
) indicates the value of the hash table for n'.

〔Effect of the invention〕

As explained above, according to the present invention, the chain of the chained hash method is made into a B* tree structure, so that the width of the hash is n
If the number of one component is m, the time required for search is O(l
og (m/m)), the time required for searching can be reduced even when the number of names becomes large compared to the conventional name table search method using the chain hash method. This has the effect of making it possible to create a memory-efficient name table.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention. FIG. 2 is a format of a name table according to an embodiment of the present invention. FIG. 3 is a flowchart showing the operation flow of the name table name registration means according to an embodiment of the present invention. 4th t! 1 is a flowchart showing the operation flow of the name table search means according to the embodiment of the present invention. 1-1... Definition work file, 1-2... Name table name registration means, 1-3... Name table,
1-4...Reference work file, l-5...Name table search means. Real brother example, ￥i 1 Picture bag example name Cheeru mark % go stage ρ movement I T 昂 3 zu 昂圓

Claims (1)

[Claims] 1. A name table having a hash table,
In a name table search device that registers and searches for names in the name table using the chain hash method, a chain of names in the name table having the same hash value is extracted from the definition work file and stored in the B tree structure as described above. A name table name registration means for registering names in a name table, and a name table search means for extracting names from a reference work file, calculating a hash value, and searching for names chained in a B tree structure from the hash table. A name table search device comprising: