Substation Configuration Description File Comparison Method, System, Medium, Device and Product

Abstract

The present invention belongs to the field of substation design, and provides a method, system, medium, device and product for comparing substation configuration description files. The technical solution is as follows: compare the contents of each sub-node in two SCD files to be compared, and store the comparison results in a data structure; the comparison process includes: taking the first SCD file as the reference file, traversing the specified nodes of the first SCD file, and according to the unique attribute identifier of the node and the check code calculated based on the node content, check whether there are corresponding nodes and different node data in the second SCD file, and store the different node data as change items in the data structure; taking the second SCD file as the reference file, traversing the specified nodes of the second SCD file, searching for the corresponding nodes in the first SCD file, and storing the nodes that are not searched as new items in the data structure. The accuracy of positioning and comparison is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of substation automation, and particularly relates to a method for generating a node difference report based on comparison of substation SCD files. Background Art

[0002] The statements in this part only provide background technical information related to the present invention and do not necessarily constitute prior art.

[0003] The Substation Configuration Description (SCD) file plays a very crucial role in the commissioning and operation process of substations.

[0004] The invention discovers that currently, during the commissioning, operation and maintenance of SCD files, due to the frequent changes of SCD files, the differences between various versions cause repeated commissioning work for commissioning personnel. For this problem, the existing solutions are as follows:

[0005] 1. When comparing different versions of existing SCD files, the contents of different files are stored in their respective arrays, and the characters are compared line by line to mark the differences. This method does not pay attention to the specific content of the SCD file and only marks the difference points. In the case of a large number of devices in the substation, it will consume a lot of time and the comparison efficiency is low;

[0006] 2. A data model and a communication service model are preset. According to the set data model, combined with the data attributes of the nodes, different versions of SCD files are compared. According to the set communication service model, all nodes that perform information interaction in different versions are compared. Although this method considers the specific content of the SCD file, it still needs to construct a data model and a communication service model. In the case of a large number of devices and equipment in the substation, it is obvious that a large amount of work is required to construct the data model and the communication service model. Summary of the Invention

[0007] In order to solve at least one of the technical problems in the above background art, the present invention provides a method, system, medium, device and product for comparing substation configuration description files, which proposes a method for structurally comparing SCD files, pays attention to the specific content of the SCD file, deeply traverses each node, and purposefully conducts comparison. For nodes without a unique identification attribute, the method of calculating and comparing check codes is adopted, and the difference points are stored through a data structure, improving the accuracy of positioning and comparison.

[0008] In order to achieve the above object, the present invention adopts the following technical solutions:

[0009] The first aspect of the present invention provides a method for comparing substation configuration description files, including the following steps:

[0010] Read the content of each sub-node in the two SCD files to be compared;

[0011] Compare the content of each sub-node in the two SCD files to be compared, and store the comparison result in a data structure; among them, the comparison process of the content of each sub-node in the two SCD files to be compared includes:

[0012] Take the first SCD file as the reference file, traverse the specified nodes of the first SCD file, and based on the unique attribute identifier of the node and the check code calculated based on the node content, check whether there are corresponding nodes and different node data in the second SCD file, and store the different node data as change items in the data structure;

[0013] Take the second SCD file as the reference file, traverse the specified nodes of the second SCD file, search for the corresponding nodes in the first SCD file, and store the nodes that are not searched as new items in the data structure.

[0014] Further, the process of checking whether there are corresponding nodes and different node data in the second SCD file based on the unique attribute identifier of the node and the check code calculated based on the node content includes:

[0015] Judge whether the comparison node has a unique identifier attribute;

[0016] If it has, search for the node corresponding to the node to be compared in the second SCD file according to the value of the unique identifier attribute of the node to be compared. If it exists, compare the attribute values of the node corresponding to the node to be compared. If the attribute values are different, store them in the change items of the data structure;

[0017] If not, first delete all attributes of the node to be compared, calculate the check code C1 of the node to be compared, then traverse the corresponding nodes in the second SCD file, calculate the check code C2, compare C1 and C2, and judge whether C1 and C2 are equal. If they are equal, the two are the same node, and further compare the attribute values of the nodes. If the attribute values of the nodes are different, store them in the change items of the data structure.

[0018] Further, the calculation methods of the check code C1 and the check code C2 are: calculate according to the content sequence of the extracted CRS check code, and the calculation rules include:

[0019] First, delete the spaces, line breaks, carriage returns, and list symbols between elements and between attributes;

[0020] Second, sort all the extracted element attributes in alphabetical order a-z;

[0021] Third, elements without child elements and assignments end with " / >";

[0022] Fourth, the sequence is converted to a UTF-8 sequence, and the four-byte CRC-32 checksum is calculated. For those with less than four bytes, the high bytes are filled with 0x0.

[0023] Further, if there is no node corresponding to the node to be compared in the second SCD file, it indicates that the corresponding node in the second SCD file has been deleted, and it is stored in the deletion item of the data structure.

[0024] Further, if the checksum C1 and C2 are not equal and there is no node in the second SCD file that is the same as the checksum C1, it indicates that the node in the second SCD file that is the same as the checksum C1 has been deleted, and it is stored in the deletion item of the data structure.

[0025] Further, after obtaining the data structure, a difference report is generated based on the comparison results stored in the data structure.

[0026] The second aspect of the present invention provides a substation configuration description file comparison system, including:

[0027] A data reading module, which is used to read the content of each sub-node in two SCD files to be compared;

[0028] A file comparison module, which is used to compare the content of each sub-node in two SCD files to be compared and store the comparison results in a data structure; wherein, the comparison process of the content of each sub-node in the two SCD files to be compared includes:

[0029] Taking the first SCD file as the reference file, traversing the specified nodes of the first SCD file, and according to the unique attribute identifier of the node and the checksum calculated based on the node content, searching in the second SCD file for whether there are corresponding nodes and node data with differences, and taking the node data with differences as change items and storing them in the data structure;

[0030] Taking the second SCD file as the reference file, traversing the specified nodes of the second SCD file, searching for the corresponding nodes in the first SCD file, and taking the node data that has not been searched as new items and storing them in the data structure.

[0031] The third aspect of the present invention provides a computer-readable storage medium.

[0032] A computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, it implements the steps in the substation configuration description file comparison method as described above.

[0033] The fourth aspect of the present invention provides a computer device.

[0034] A computer device includes a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the steps in the substation configuration description file comparison method as described above are implemented.

[0035] The fifth aspect of the present invention provides a program product.

[0036] The program product is a computer program product, including a computer program. When the computer program is executed by a processor, the steps in the substation configuration description file comparison method as described above are implemented.

[0037] Compared with the prior art, the beneficial effects of the present invention are:

[0038] 1. When comparing different versions of SCD files in the prior art, the specific content of the SCD file is not concerned. The present invention improves the accuracy of positioning and comparison by focusing on the specific content of the SCD file, deeply traversing each node, separately comparing the contents of each sub-node, and processing the nodes with unique identifier attributes and the nodes without unique identifier attributes in their respective ways.

[0039] 2. After the current SCD file comparison, different data are marked in a marked way and then manually classified and summarized, resulting in low efficiency. The present invention stores the different nodes in the deletion item by using a data structure, and the deleted nodes are also stored in the deletion item. On this basis, further processing is carried out, and the comparison result can be directly called to generate a report for display, giving a guiding hint for easy analysis and processing.

[0040] The advantages of the additional aspects of the present invention will be partially given in the following description, partially will become obvious from the following description, or will be understood through the practice of the present invention. Description of the Drawings

[0041] The specification drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0042] Figure 1 It is the overall flowchart of the substation configuration description file comparison method provided by the embodiment of the present invention;

[0043] Figure 2 It is the detailed comparison flowchart of the substation configuration description file comparison method provided by the embodiment of the present invention. Detailed Embodiments

[0044] The present invention will be further described below in conjunction with the drawings and embodiments.

[0045] It should be noted that the following detailed description is illustrative and aims to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention pertains.

[0046] It should be noted that the terms used herein are merely for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they specify the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0047] In view of the technical problems existing in the comparison of different existing versions of SCD files mentioned in the background art of the present application, the present invention provides a method for structurally comparing SCD files, mainly including the following improvements:

[0048] 1. When comparing different existing versions of SCD files, the specific content of the SCD files is not concerned. The present invention improves the accuracy of positioning and comparison by focusing on the specific content of the SCD files, deeply traversing each node, respectively comparing the contents of each sub-node, and processing the nodes with unique identifier attributes and the nodes without unique identifier attributes in their respective ways.

[0049] 2. After the current comparison of SCD files, different data are marked by a marking method and then manually classified and summarized, resulting in low efficiency. The present invention stores the different nodes in a deletion item by using a data structure, and the deleted nodes are also stored in the deletion item. Based on this, further processing is carried out, and the comparison results can be directly displayed by calling the data structure subsequently.

[0050] Embodiment 1

[0051] As Figure 1 shown, this embodiment provides a method for comparing substation configuration description files, including the following steps:

[0052] Step 1: Read the contents of each sub-node in two SCD files to be compared;

[0053] In this embodiment, the contents of each sub-node in the two SCD files to be compared include: Substation, Communication, IED, and DataTypeTemplates nodes of the data type model and all their sub-nodes.

[0054] Step 2: Compare the content of each sub-node in the two SCD files to be compared, obtain the difference data, and store the difference data in a data structure to generate a difference report;

[0055] As Figure 2 shown below, take the two SCD files, File A and File B, to be compared as an example to illustrate the specific comparison method, including the following steps:

[0056] Step 201: Take File A as the reference file and traverse the specified nodes of File A. Taking one of the nodes to be compared, node a, as an example, it includes the following steps:

[0057] Step 2011: Determine whether the node to be compared, node a, has a unique identifier attribute;

[0058] Step 2012: If it does, find the corresponding node b in File B according to the value of the unique identifier attribute of the node to be compared, node a. If it exists, compare the attribute values of the corresponding node b of the node to be compared, node a. If there are differences in the attribute values, store them in the change item of the data structure. If not, it means that the corresponding node b in File B has been deleted, and store it in the deletion item of the data structure;

[0059] Step 2013: If not, first delete all the attributes of the node to be compared, node a, and calculate the check code C1 of the node to be compared, node a. Then traverse the corresponding nodes in File B and calculate the check code C2 in the same way. Compare C1 and C2 to determine whether C1 and C2 are equal. If they are equal, the two are the same node, and further compare the attribute values of the nodes. If there are differences in the attribute values of the nodes, store them in the change item of the data structure. Otherwise, there is no node in File B with the same check code C1, which means that the node with the same check code C1 in File B has been deleted, and store it in the deletion item of the data structure;

[0060] In this embodiment, the calculation methods of the check code C1 and the check code C2 of the node to be compared, node a, are as follows: Extract the content sequence used to calculate the CRC check code, and the calculation rules include:

[0061] (1) Delete the spaces, line breaks, carriage returns, and list symbols between elements and attributes;

[0062] (2) Arrange all the extracted element attributes in alphabetical order a-z;

[0063] (3) Elements without sub-elements and assignments end with " / >";

[0064] (4)The sequence is converted into a UTF-8 sequence, and a 4-byte CRC-32 checksum is calculated. For those less than 4 bytes, the high bytes are filled with 0x0. CRC calculation parameters: number of bits Width = 32; generating item Poly = 04C11DB7; initial value Init = FFFFFFFF; whether the data to be tested is reversed RefIn = True; whether the calculated value is reversed RefOut = True; exclusive-OR item of the output data XorOut = FFFFFFFF.

[0065] Step 2014: Repeat steps 2011 - 2013 until all the specified nodes in file A are completely compared.

[0066] Step 202: Take file B as the reference file, traverse the specified nodes, search for the corresponding nodes in file A. If they do not exist, it means these nodes do not exist in file A and are new nodes, which are stored as new items in the new item of the data structure.

[0067] It should be noted that in this embodiment, the checksum can be CRC (Cyclic Redundancy Check) checksum, parity check, MD5, SHA1, etc. There is no specific limitation in this embodiment, and it can be selected according to the actual situation;

[0068] In this embodiment, the data structure can adopt a custom struct structure type, as shown below:

[0069] typedef struct _DiffInf / / Difference information

[0070] {

[0071] QString oldVersion; / / Original version number

[0072] QString oldRevision; / / Original revision version number

[0073] QString newVersion; / / New version number

[0074] QString newRevision; / / New revision version number

[0075] QList<s_IEDRename> changedIEDs; / / Changed category: secondary equipment

[0076] QList<s_SNet changedStationInfos; / / Changed category: substation control layer network parameters

[0077] QMap<QString, QList<s_GOOSEAttr>> changedGOOSEInfos; / / Changed class: Process layer GOOSE parameters

[0078] QMap<QString, QList<s_SMVAttr>> changedSMVInfos; / / Changed class: Process layer SMV parameters

[0079] QStringList deletedIEDs; / / Deleted class; Secondary equipment

[0080] QMap<QString, QList<s_GOOSEAttr>> deletedGOOSEInfos; / / Deleted class: Process layer GOOSE parameters

[0081] QMap<QString, QList<s_SMVAttr>> deletedSMVInfos; / / Deleted class: Process layer SMV parameters

[0082] QStringList addedIEDs; / / Added class: Secondary equipment

[0083] QMap<QString, QList<s_GOOSEAttr>> addedGOOSEInfos; / / Added class: Process layer GOOSE parameters

[0084] QMap<QString, QList<s_SMVAttr>> addedSMVInfos; / / Added class: Process layer SMV parameters

[0085] }s_DiffInf;

[0086] Step 3: Destroy the two SCD file objects to be compared and release the memory space;

[0087] In this embodiment, to destroy the two SCD file objects to be compared and release the memory space, explicit object deletion or setting the object to None can be used, which can be determined according to the specific application scenario and programming language environment.

[0088] Step 4: Extract and generate the information for the difference report for display according to the data structure, and give guiding hints for easy analysis and processing.

[0089] In this embodiment, the results are displayed in tabular form, which is concise and intuitive; the report is in XML format and can be displayed across machines and platforms. As shown in Table 1, the comparison results of the two SCD files are displayed.

[0090] Table 1 Comparison Results of Two SCD Files

[0091]

[0092] As can be seen from Table 1, the differential data in the comparison results.

[0093] Embodiment 2

[0094] This embodiment provides a substation configuration description file comparison system, including:

[0095] A data reading module, which is used to read the content of each sub-node in two SCD files to be compared;

[0096] A file comparison module, which is used to compare the content of each sub-node in two SCD files to be compared and store the comparison results in a data structure; wherein, the comparison process of the content of each sub-node in the two SCD files to be compared includes:

[0097] Taking the first SCD file as the reference file, traversing the specified nodes of the first SCD file, and according to the unique attribute identifier of the node and the check code calculated based on the node content, searching in the second SCD file for whether there is a corresponding node and the node data with differences, and taking the node data with differences as change items and storing them in the data structure;

[0098] Taking the second SCD file as the reference file, traversing the specified nodes of the second SCD file, searching for the corresponding nodes in the first SCD file, and taking the node data not searched as new items and storing them in the data structure.

[0099] Among them, in the file comparison module, the searching in the second SCD file for whether there is a corresponding node and the node data with differences according to the unique attribute identifier of the node and the check code calculated based on the node content includes:

[0100] Judging whether the comparison node has a unique identifier attribute;

[0101] If so, searching in the second SCD file for the node corresponding to the node to be compared according to the value of the unique identifier attribute of the node to be compared. If it exists, comparing the attribute values of the node corresponding to the node to be compared. If the attribute values are different, storing them in the change items of the data structure;

[0102] If not, first deleting all attributes of the node to be compared, calculating the check code C1 of the node to be compared, then traversing the corresponding nodes in file B, calculating the check code C2, comparing C1 and C2, judging whether C1 and C2 are equal. If they are equal, the two are the same node, and further comparing the attribute values of the nodes. If the attribute values of the nodes are different, storing them in the change items of the data structure.

[0103] Among them, the calculation methods of the check codes C1 and C2 are as follows: Calculate according to the content sequence of the extracted CRS check code, and the calculation rules include:

[0104] (1) Delete the spaces, line breaks, carriage returns, and list symbols between elements and between attributes;

[0105] (2) Arrange all the extracted element attributes in alphabetical order a - z;

[0106] (3) Elements without sub - elements and assignments end with " / >";

[0107] (4) Convert the sequence to a UTF - 8 sequence, calculate the 4 - byte CRC - 32 check code. For those less than 4 bytes, fill the high - byte with 0x0.

[0108] Embodiment III

[0109] This embodiment provides a computer - readable storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the steps in the substation configuration description file comparison method as described above.

[0110] Embodiment IV

[0111] This embodiment provides a computer device, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, it implements the steps in the substation configuration description file comparison method as described above.

[0112] Embodiment V

[0113] This embodiment provides a program product, which is a computer program product, including a computer program. When the computer program is executed by a processor, it implements the steps in the substation configuration description file comparison method as described above.

[0114] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a hardware embodiment, a software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer - usable storage media (including but not limited to disk storage and optical storage, etc.) containing computer - usable program code.

[0115] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate a means for implementing the functions specified in one process Figure 1 one process or multiple processes and / or blocks Figure 1 or a means for implementing the functions specified in multiple blocks.

[0116] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including an instruction means that implements the functions specified in one process Figure 1 one process or multiple processes and / or blocks Figure 1 or a means for implementing the functions specified in multiple blocks.

[0117] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one process Figure 1 one process or multiple processes and / or blocks Figure 1 or a means for implementing the functions specified in multiple blocks.

[0118] Those of ordinary skill in the art can understand that all or part of the processes in the above-described method embodiments can be completed by instructing relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the above-described method embodiments. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM), etc.

[0119] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for comparing substation configuration description files, characterized in that Including: Read the content of each sub-node in two SCD files to be compared; Compare the content of each sub-node in the two SCD files to be compared, and store the comparison result in a data structure; wherein, the comparison process of the content of each sub-node in the two SCD files to be compared includes: Take the first SCD file as the reference file, traverse the specified nodes of the first SCD file, and based on the unique attribute identifier of the node and the checksum calculated based on the node content, check whether there are corresponding nodes and different node data in the second SCD file, and store the different node data as change items in the data structure; The step of checking whether there are corresponding nodes and different node data in the second SCD file according to the unique attribute identifier of the node and the checksum calculated based on the node content includes: Judge whether the comparison node has a unique identifier attribute; If so, find the node corresponding to the node to be compared in the second SCD file according to the value of the unique identifier attribute of the node to be compared. If it exists, compare the attribute values of the node corresponding to the node to be compared. If the attribute values are different, store them in the change items of the data structure; If not, first delete all attributes of the node to be compared, calculate the checksum C1 of the node to be compared, then traverse the corresponding nodes in the second SCD file, calculate the checksum C2, compare C1 and C2, and judge whether C1 and C2 are equal. If they are equal, the two are the same node, and further compare the attribute values of the nodes. If the attribute values of the nodes are different, store them in the change items of the data structure; Take the second SCD file as the reference file, traverse the specified nodes of the second SCD file, search for the corresponding nodes in the first SCD file, and store the un-searched node data as new items in the data structure.

2. The substation configuration description file comparison method according to claim 1, characterized in that, The calculation methods of the checksum C1 and the checksum C2 are: calculate according to the content sequence of the extracted CRS checksum, and the calculation rules include: First, delete the spaces, line breaks, carriage returns, and list symbols between elements and attributes; Second, sort all the extracted element attributes in alphabetical order a-z; Third, elements without sub-elements and assignments end with " / >"; Fourth, convert the sequence to a UTF-8 sequence, calculate the four-byte CRC-32 checksum, and for those with less than four bytes, fill the high bytes with 0x0.

3. The substation configuration description file comparison method according to claim 1, wherein, If there is no node corresponding to the node to be compared in the second SCD file, it means that the corresponding node in the second SCD file has been deleted, and store it in the deletion items of the data structure.

4. The substation configuration description file comparison method according to claim 1, wherein, If the checksum C1 and C2 are not equal and there is no node in the second SCD file that is the same as the checksum C1, it means that the node in the second SCD file that is the same as the checksum C1 has been deleted, and store it in the deletion items of the data structure.

5. The substation configuration description file comparison method according to claim 1, characterized in that After obtaining the data structure, generate a difference report based on the comparison result stored in the data structure.

6. A substation configuration description file comparison system, characterized in that, Including: A data reading module, which is used to read the content of each sub-node in two SCD files to be compared; A file comparison module, which is used to compare the content of each sub-node in two SCD files to be compared and store the comparison result in a data structure; wherein, the comparison process of the content of each sub-node in the two SCD files to be compared includes: Taking the first SCD file as the reference file, traversing the specified nodes of the first SCD file, and searching in the second SCD file for whether there are corresponding nodes and node data with differences according to the unique attribute identifier of the node and the check code calculated based on the node content, and storing the node data with differences as change items in the data structure; The searching in the second SCD file for whether there are corresponding nodes and node data with differences according to the unique attribute identifier of the node and the check code calculated based on the node content includes: Judging whether the comparison node has a unique identifier attribute; If so, searching in the second SCD file for the node corresponding to the node to be compared according to the value of the unique identifier attribute of the node to be compared. If it exists, comparing the attribute values of the node corresponding to the node to be compared. If the attribute values are different, storing them in the change items of the data structure; If not, first deleting all attributes of the node to be compared, calculating the check code C1 of the node to be compared, then traversing the corresponding nodes in the second SCD file, calculating the check code C2, comparing C1 and C2, judging whether C1 and C2 are equal. If they are equal, the two are the same node, and further comparing the attribute values of the nodes. If the attribute values of the nodes are different, storing them in the change items of the data structure; Taking the second SCD file as the reference file, traversing the specified nodes of the second SCD file, searching for the corresponding nodes in the first SCD file, and storing the node data not searched as new items in the data structure.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the program is executed by a processor, it implements the steps in the substation configuration description file comparison method according to any one of claims 1-5.

8. A computer device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps in the substation configuration description file comparison method according to any one of claims 1-5.

9. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps in the substation configuration description file comparison method according to any one of claims 1-5.

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