From d994d70cc2218c88980af457b97245e6911f1ec9 Mon Sep 17 00:00:00 2001 From: Zur Aogav Date: Tue, 1 Aug 2023 15:15:36 +0300 Subject: [PATCH] DIMACS IO Implementation --- .../main/java/com/jgalgo/io/FormatDIMACS.java | 155 +++++++++++++++++- .../java/com/jgalgo/io/FormatDIMACSTest.java | 118 +++++++++++++ 2 files changed, 268 insertions(+), 5 deletions(-) create mode 100644 jgalgo-io/src/test/java/com/jgalgo/io/FormatDIMACSTest.java diff --git a/jgalgo-io/src/main/java/com/jgalgo/io/FormatDIMACS.java b/jgalgo-io/src/main/java/com/jgalgo/io/FormatDIMACS.java index f1cceb09f6..cafdd055c0 100644 --- a/jgalgo-io/src/main/java/com/jgalgo/io/FormatDIMACS.java +++ b/jgalgo-io/src/main/java/com/jgalgo/io/FormatDIMACS.java @@ -15,15 +15,21 @@ */ package com.jgalgo.io; +import java.io.BufferedReader; +import java.io.IOException; import java.io.Reader; +import java.io.UncheckedIOException; import java.io.Writer; import java.util.List; + import com.jgalgo.graph.Graph; import com.jgalgo.graph.GraphBuilder; +import com.jgalgo.graph.Weights; class FormatDIMACS implements GraphFormat { - private FormatDIMACS() {} + private FormatDIMACS() { + } static final FormatDIMACS Instance = new FormatDIMACS(); @@ -48,18 +54,157 @@ private static class WriterImpl implements GraphWriter { @Override public void writeGraph(Graph graph, Writer writer) { - // TODO Auto-generated method stub - throw new UnsupportedOperationException("Unimplemented method 'writeGraph'"); + try { + writer.append("c DIMACS written graph by JGAlgo") // + .append(System.lineSeparator()); + final int num_vertices = graph.vertices().size(); + final int num_edges = graph.edges().size(); + final Weights.Int w = graph.getEdgesWeights("weightsEdges"); + final boolean hash_weights = w != null; + if (hash_weights) + writer.append("p sp " + num_vertices + " " + num_edges) // + .append(System.lineSeparator()); + else + writer.append("p edge " + num_vertices + " " + num_edges) // + .append(System.lineSeparator()); + + // writes all edges, optional with weights + for (int e : graph.edges()) { + writer.append("e " + graph.edgeSource(e) + " " + graph.edgeTarget(e)); + if (hash_weights) { + int the_weight = w.getInt(e); + writer.append(" " + the_weight); + } + writer.append(System.lineSeparator()); + } + + } catch (IOException e) { + throw new UncheckedIOException(e); + } + } } private static class ReaderImpl implements GraphReader { + /** + * Support 2 DIMACS formats:
+ * The "DIMACS edge format" and "DIMACS sp format"
+ *
+ * 1. Basic DIMACS format:
+ * see https://github.com/akinanop/mvl-solver/wiki/DIMACS-Graph-Format + * + * 
+		p edge  
+		e  
+		Example:
+		c this is the graph with vertices {1,2,3,4,5} and edges {(1,2),(2,3),(2,4),(3,4),(4,5)}
+		p edge 5 5
+		e 1 2
+		e 2 3
+		e 2 4
+		e 3 4
+		e 4 5
+		 *
+ * + * 2. Shortest path format (with weights)
+ * Two assumptions:
+ * (1) Undirected graph.
+ * (2) Weights are integers.
+ *
+ * The .gr files:
+ * see http://www.diag.uniroma1.it/challenge9/format.shtml#graph + * + * 
+			c
+			p sp n nm
+			a u v w
+		 *
+ */ @Override public GraphBuilder readIntoBuilder(Reader reader) { - // TODO Auto-generated method stub - throw new UnsupportedOperationException("Unimplemented method 'readIntoBuilder'"); + try (BufferedReader br = reader instanceof BufferedReader ? (BufferedReader) reader + : new BufferedReader(reader)) { + GraphBuilder gb = null; + Weights.Int w = null; + String line; + String graph_format = null; + int num_vertices = -1; + int num_edges = -1; + while ((line = br.readLine()) != null) { + // skip empty and comment lines (starts with "c") + if (line.trim().length() == 0 || line.trim().startsWith("c")) + continue; + // replace multiple spaces with just one space + line = line.trim().replaceAll("\\s+", " "); + if (line.trim().startsWith("p")) { + String[] arr = line.split(" "); + if (arr.length < 4) + throw new IllegalArgumentException( + "p lines must have 4 parameters: p edge or p sp "); + graph_format = arr[1].toLowerCase(); + if (!(graph_format.equals("sp") || graph_format.equals("edge"))) + throw new IllegalArgumentException( + "support only: p edge or p sp "); + try { + num_vertices = Integer.parseInt(arr[2]); + num_edges = Integer.parseInt(arr[3]); + } catch (Exception e) { + throw new IllegalArgumentException( + "expect numbers: p edge or p sp "); + } + if (num_vertices < 1) + return gb; + gb = GraphBuilder.newUndirected(); + if (graph_format.equals("sp")) + w = gb.addEdgesWeights("weightsEdges", int.class); + for (int i = 0; i < num_vertices; i++) + gb.addVertex(i + 1); // vertices are labeled as 1,2,3,4... + if (num_edges < 1) + return gb; + continue; + } + + // here, we expect edge definition + // e source_vertice destination_vertice [weight] + if (!line.trim().toLowerCase().startsWith("e")) + throw new IllegalArgumentException( + "expect edge definition: e "); + String[] arr = line.split(" "); + if (graph_format.equals("sp") && arr.length < 4) + throw new IllegalArgumentException( + "expect edge definition: e "); + if (graph_format.equals("edge") && arr.length < 3) + throw new IllegalArgumentException( + "expect edge definition: e "); + int vertice_source = -1; + int vertice_target = -1; + int edge_weight = -1; + try { + vertice_source = Integer.parseInt(arr[1]); + vertice_target = Integer.parseInt(arr[2]); + if (graph_format.equals("sp")) + edge_weight = Integer.parseInt(arr[3]); + } catch (Exception e) { + if (graph_format.equals("sp")) + throw new IllegalArgumentException("edge must have 2 vertices as numbers and a weight"); + throw new IllegalArgumentException("edge must have 2 vertices as numbers"); + } + if (vertice_source < 1 || vertice_source > num_vertices // + || vertice_target < 1 || vertice_target > num_vertices) + throw new IllegalArgumentException("vertice nmber must be betwen 1 and num_vertices"); + // vertices labels 1..num_vertices are mapped to 0..num_vertices-1 + final int e = gb.addEdge(vertice_source, vertice_target); + if (graph_format.equals("sp")) + w.set(e, edge_weight); + continue; + } + return gb; + + } catch (IOException e) { + throw new UncheckedIOException(e); + } } } diff --git a/jgalgo-io/src/test/java/com/jgalgo/io/FormatDIMACSTest.java b/jgalgo-io/src/test/java/com/jgalgo/io/FormatDIMACSTest.java new file mode 100644 index 0000000000..d659f0471f --- /dev/null +++ b/jgalgo-io/src/test/java/com/jgalgo/io/FormatDIMACSTest.java @@ -0,0 +1,118 @@ +/*- + * Copyright 2023 Barak Ugav + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +package com.jgalgo.io; + +import static org.junit.jupiter.api.Assertions.assertEquals; +import static org.junit.jupiter.api.Assertions.assertThrows; +import java.io.StringReader; +import java.io.StringWriter; +import java.util.Random; +import org.junit.jupiter.api.Test; +import com.jgalgo.graph.Graph; +import com.jgalgo.graph.GraphBuilder; +import com.jgalgo.graph.GraphFactory; +import com.jgalgo.graph.Weights; + +public class FormatDIMACSTest { + + @Test + public void parseDimacsEdgeGraph() { + String data = ""; + data += "c this is the graph with vertices {1,2,3,4,5} and edges {(1,2),(2,3),(2,4),(3,4),(4,5)}\n"; + data += "p edge 5 5\n"; + data += "e 1 2\n"; + data += "e 2 3\n"; + data += "e 2 4\n"; + data += "e 3 4\n"; + data += "e 4 5\n"; + final Graph g = GraphReader.newInstance("dimacs").readGraph(new StringReader(data)); + + final StringWriter writer = new StringWriter(); + GraphWriter.newInstance("dimacs").writeGraph(g, writer); + String data2 = writer.toString(); + + String check_data2 = ""; + check_data2 += "c DIMACS written graph by JGAlgo\n"; + check_data2 += "p edge 5 5\n"; + check_data2 += "e 1 2\n"; + check_data2 += "e 2 3\n"; + check_data2 += "e 2 4\n"; + check_data2 += "e 3 4\n"; + check_data2 += "e 4 5\n"; + check_data2 = check_data2.replace("\n", System.lineSeparator()); + String check_data3 = ""; + check_data3 += "c DIMACS written graph by JGAlgo\n"; + check_data3 += "p edge 5 5\n"; + check_data3 += "e 1 2\n"; + check_data3 += "e 2 4\n"; + check_data3 += "e 2 3\n"; + check_data3 += "e 3 4\n"; + check_data3 += "e 4 5\n"; + check_data3 = check_data3.replace("\n", System.lineSeparator()); + + if (data2.trim().equals(check_data2.trim())) + assertEquals(data2.trim(), check_data2.trim()); + else if (data2.trim().equals(check_data3.trim())) + assertEquals(data2.trim(), check_data3.trim()); + else + assertEquals(data2.trim(), check_data2.trim()); + } + + @Test + public void parseDimacsSpGraph() { + String data = ""; + data += "c this is the graph\n"; + data += "p sp 5 5\n"; + data += "e 1 2 3\n"; + data += "e 2 3 9\n"; + data += "e 2 4 15\n"; + data += "e 3 4 2\n"; + data += "e 4 5 7\n"; + final Graph g = GraphReader.newInstance("dimacs").readGraph(new StringReader(data)); + + final StringWriter writer = new StringWriter(); + GraphWriter.newInstance("dimacs").writeGraph(g, writer); + String data2 = writer.toString(); + + String check_data2 = ""; + check_data2 += "c DIMACS written graph by JGAlgo\n"; + check_data2 += "p sp 5 5\n"; + check_data2 += "e 1 2 3\n"; + check_data2 += "e 2 3 9\n"; + check_data2 += "e 2 4 15\n"; + check_data2 += "e 3 4 2\n"; + check_data2 += "e 4 5 7\n"; + check_data2 = check_data2.replace("\n", System.lineSeparator()); + String check_data3 = ""; + check_data3 += "c DIMACS written graph by JGAlgo\n"; + check_data3 += "p sp 5 5\n"; + check_data3 += "e 1 2 3\n"; + check_data3 += "e 2 4 15\n"; + check_data3 += "e 2 3 9\n"; + check_data3 += "e 3 4 2\n"; + check_data3 += "e 4 5 7\n"; + check_data3 = check_data3.replace("\n", System.lineSeparator()); + + if (data2.trim().equals(check_data2.trim())) + assertEquals(data2.trim(), check_data2.trim()); + else if (data2.trim().equals(check_data3.trim())) + assertEquals(data2.trim(), check_data3.trim()); + else + assertEquals(data2.trim(), check_data2.trim()); + } + +}