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addEdge fix

This commit is contained in:
pazis 2019-11-24 18:40:13 +00:00
parent d1bd33f862
commit 24859d45ab
4 changed files with 40 additions and 37 deletions
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3
algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/prim/Edge.java
View File

@ -6,7 +6,7 @@ public class Edge {
private boolean isIncluded = false; private boolean isIncluded = false;
private boolean isPrinted = false; private boolean isPrinted = false;
public Edge (int weight){ public Edge(int weight) {
this.weight = weight; this.weight = weight;
} }
@ -34,4 +34,3 @@ public class Edge {
isPrinted = printed; isPrinted = printed;
} }
} }

43
algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/prim/Prim.java
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@ -10,21 +10,23 @@ public class Prim {
private List<Vertex> graph; private List<Vertex> graph;
public Prim(List<Vertex> graph){ public Prim(List<Vertex> graph) {
this.graph = graph; this.graph = graph;
} }
public void run(){ public void run() {
if (graph.size() > 0){ if (graph.size() > 0) {
graph.get(0).setVisited(true); graph.get(0)
.setVisited(true);
} }
while (isDisconnected()){ while (isDisconnected()) {
Edge nextMinimum = new Edge(Integer.MAX_VALUE); Edge nextMinimum = new Edge(Integer.MAX_VALUE);
Vertex nextVertex = graph.get(0); Vertex nextVertex = graph.get(0);
for (Vertex vertex : graph){ for (Vertex vertex : graph) {
if (vertex.isVisited()){ if (vertex.isVisited()) {
Pair<Vertex, Edge> candidate = vertex.nextMinimum(); Pair<Vertex, Edge> candidate = vertex.nextMinimum();
if (candidate.getValue().getWeight() < nextMinimum.getWeight()){ if (candidate.getValue()
.getWeight() < nextMinimum.getWeight()) {
nextMinimum = candidate.getValue(); nextMinimum = candidate.getValue();
nextVertex = candidate.getKey(); nextVertex = candidate.getKey();
} }
@ -35,40 +37,41 @@ public class Prim {
} }
} }
private boolean isDisconnected(){ private boolean isDisconnected() {
for (Vertex vertex : graph){ for (Vertex vertex : graph) {
if (!vertex.isVisited()){ if (!vertex.isVisited()) {
return true; return true;
} }
} }
return false; return false;
} }
public String originalGraphToString(){ public String originalGraphToString() {
StringBuilder sb = new StringBuilder(); StringBuilder sb = new StringBuilder();
for (Vertex vertex : graph){ for (Vertex vertex : graph) {
sb.append(vertex.originalToString()); sb.append(vertex.originalToString());
} }
return sb.toString(); return sb.toString();
} }
public void resetPrintHistory(){ public void resetPrintHistory() {
for (Vertex vertex : graph){ for (Vertex vertex : graph) {
Iterator it = vertex.getEdges().entrySet().iterator(); Iterator it = vertex.getEdges()
.entrySet()
.iterator();
while (it.hasNext()) { while (it.hasNext()) {
Map.Entry pair = (Map.Entry) it.next(); Map.Entry pair = (Map.Entry) it.next();
((Edge)pair.getValue()).setPrinted(false); ((Edge) pair.getValue()).setPrinted(false);
} }
} }
} }
public String minimumSpanningTreeToString(){ public String minimumSpanningTreeToString() {
StringBuilder sb = new StringBuilder(); StringBuilder sb = new StringBuilder();
for (Vertex vertex : graph){ for (Vertex vertex : graph) {
sb.append(vertex.includedToString()); sb.append(vertex.includedToString());
} }
return sb.toString(); return sb.toString();
} }
} }

28
algorithms-miscellaneous-5/src/main/java/com/baeldung/algorithms/prim/Vertex.java
View File

@ -12,7 +12,7 @@ public class Vertex {
private Map<Vertex, Edge> edges = new HashMap<>(); private Map<Vertex, Edge> edges = new HashMap<>();
private boolean isVisited = false; private boolean isVisited = false;
public Vertex(String label){ public Vertex(String label) {
this.label = label; this.label = label;
} }
@ -28,7 +28,7 @@ public class Vertex {
return edges; return edges;
} }
public void addEdge(Vertex vertex, Edge edge){ public void addEdge(Vertex vertex, Edge edge) {
this.edges.put(vertex, edge); this.edges.put(vertex, edge);
} }
@ -40,14 +40,15 @@ public class Vertex {
isVisited = visited; isVisited = visited;
} }
public Pair<Vertex, Edge> nextMinimum(){ public Pair<Vertex, Edge> nextMinimum() {
Edge nextMinimum = new Edge(Integer.MAX_VALUE); Edge nextMinimum = new Edge(Integer.MAX_VALUE);
Vertex nextVertex = this; Vertex nextVertex = this;
Iterator it = edges.entrySet().iterator(); Iterator it = edges.entrySet()
.iterator();
while (it.hasNext()) { while (it.hasNext()) {
Map.Entry pair = (Map.Entry) it.next(); Map.Entry pair = (Map.Entry) it.next();
if (!((Vertex)pair.getKey()).isVisited()){ if (!((Vertex) pair.getKey()).isVisited()) {
if (!((Edge)pair.getValue()).isIncluded()) { if (!((Edge) pair.getValue()).isIncluded()) {
if (((Edge) pair.getValue()).getWeight() < nextMinimum.getWeight()) { if (((Edge) pair.getValue()).getWeight() < nextMinimum.getWeight()) {
nextMinimum = (Edge) pair.getValue(); nextMinimum = (Edge) pair.getValue();
nextVertex = (Vertex) pair.getKey(); nextVertex = (Vertex) pair.getKey();
@ -58,12 +59,13 @@ public class Vertex {
return new Pair<>(nextVertex, nextMinimum); return new Pair<>(nextVertex, nextMinimum);
} }
public String originalToString(){ public String originalToString() {
StringBuilder sb = new StringBuilder(); StringBuilder sb = new StringBuilder();
Iterator it = edges.entrySet().iterator(); Iterator it = edges.entrySet()
.iterator();
while (it.hasNext()) { while (it.hasNext()) {
Map.Entry pair = (Map.Entry) it.next(); Map.Entry pair = (Map.Entry) it.next();
if (!((Edge)pair.getValue()).isPrinted()) { if (!((Edge) pair.getValue()).isPrinted()) {
sb.append(getLabel()); sb.append(getLabel());
sb.append(" --- "); sb.append(" --- ");
sb.append(((Edge) pair.getValue()).getWeight()); sb.append(((Edge) pair.getValue()).getWeight());
@ -76,14 +78,15 @@ public class Vertex {
return sb.toString(); return sb.toString();
} }
public String includedToString(){ public String includedToString() {
StringBuilder sb = new StringBuilder(); StringBuilder sb = new StringBuilder();
if (isVisited()) { if (isVisited()) {
Iterator it = edges.entrySet().iterator(); Iterator it = edges.entrySet()
.iterator();
while (it.hasNext()) { while (it.hasNext()) {
Map.Entry pair = (Map.Entry) it.next(); Map.Entry pair = (Map.Entry) it.next();
if (((Edge) pair.getValue()).isIncluded()) { if (((Edge) pair.getValue()).isIncluded()) {
if (!((Edge)pair.getValue()).isPrinted()) { if (!((Edge) pair.getValue()).isPrinted()) {
sb.append(getLabel()); sb.append(getLabel());
sb.append(" --- "); sb.append(" --- ");
sb.append(((Edge) pair.getValue()).getWeight()); sb.append(((Edge) pair.getValue()).getWeight());
@ -98,4 +101,3 @@ public class Vertex {
return sb.toString(); return sb.toString();
} }
} }

3
algorithms-miscellaneous-5/src/test/java/com/baeldung/algorithms/prim/PrimUnitTest.java
View File

@ -18,7 +18,7 @@ public class PrimUnitTest {
System.out.println(prim.minimumSpanningTreeToString()); System.out.println(prim.minimumSpanningTreeToString());
} }
public static List<Vertex> createGraph(){ public static List<Vertex> createGraph() {
List<Vertex> graph = new ArrayList<>(); List<Vertex> graph = new ArrayList<>();
Vertex a = new Vertex("A"); Vertex a = new Vertex("A");
Vertex b = new Vertex("B"); Vertex b = new Vertex("B");
@ -52,4 +52,3 @@ public class PrimUnitTest {
} }
} }