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Resolve build errors & cleanup structure (#2334)

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This commit is contained in:
Andrii Siriak
2021-09-26 12:26:59 +03:00
committed by GitHub
parent 355900226a
commit dfe189b21f
48 changed files with 418 additions and 1102 deletions
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35
DataStructures/Graphs/A_Star.java
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@ -2,32 +2,33 @@
Time Complexity = O(E), where E is equal to the number of edges
*/
package A_Star;
package Graphs;
import java.lang.reflect.Array;
import java.util.*;
public class A_Star {
private static class Graph {
// Graph's structure can be changed only applying changes to this class.
private ArrayList<Edge>[] graph;
private ArrayList<ArrayList<Edge>> graph;
// Initialise ArrayLists in Constructor
public Graph(int size) {
this.graph = new ArrayList[size];
this.graph = new ArrayList<>();
for (int i = 0; i < size; i++) {
this.graph[i] = new ArrayList<>();
this.graph.set(i, new ArrayList<>());
}
}
private ArrayList<Edge> getNeighbours(int from) {
return this.graph[from];
return this.graph.get(from);
}
// Graph is bidirectional, for just one direction remove second instruction of this method.
private void addEdge(Edge edge) {
this.graph[edge.getFrom()].add(new Edge(edge.getFrom(), edge.getTo(), edge.getWeight()));
this.graph[edge.getTo()].add(new Edge(edge.getTo(), edge.getFrom(), edge.getWeight()));
this.graph.get(edge.getFrom()).add(new Edge(edge.getFrom(), edge.getTo(), edge.getWeight()));
this.graph.get(edge.getTo()).add(new Edge(edge.getTo(), edge.getFrom(), edge.getWeight()));
}
}
@ -83,7 +84,7 @@ public class A_Star {
private void printSolution() {
if (this.path != null)
System.out.println(
"Optimal path: " + this.path.toString() + ", distance: " + this.distance);
"Optimal path: " + this.path + ", distance: " + this.distance);
else System.out.println("There is no path available to connect the points");
}
}
@ -129,13 +130,13 @@ public class A_Star {
Graph graph = new Graph(20);
ArrayList<Integer> graphData =
new ArrayList<>(
Arrays.asList(
0, 19, 75, null, 0, 15, 140, null, 0, 16, 118, null, 19, 12, 71, null, 12, 15, 151,
null, 16, 9, 111, null, 9, 10, 70, null, 10, 3, 75, null, 3, 2, 120, null, 2, 14,
146, null, 2, 13, 138, null, 2, 6, 115, null, 15, 14, 80, null, 15, 5, 99, null, 14,
13, 97, null, 5, 1, 211, null, 13, 1, 101, null, 6, 1, 160, null, 1, 17, 85, null,
17, 7, 98, null, 7, 4, 86, null, 17, 18, 142, null, 18, 8, 92, null, 8, 11, 87));
new ArrayList<>(
Arrays.asList(
0, 19, 75, null, 0, 15, 140, null, 0, 16, 118, null, 19, 12, 71, null, 12, 15, 151,
null, 16, 9, 111, null, 9, 10, 70, null, 10, 3, 75, null, 3, 2, 120, null, 2, 14,
146, null, 2, 13, 138, null, 2, 6, 115, null, 15, 14, 80, null, 15, 5, 99, null, 14,
13, 97, null, 5, 1, 211, null, 13, 1, 101, null, 6, 1, 160, null, 1, 17, 85, null,
17, 7, 98, null, 7, 4, 86, null, 17, 18, 142, null, 18, 8, 92, null, 8, 11, 87));
initializeGraph(graph, graphData);
PathAndDistance solution = aStar(3, 1, graph, heuristic);
@ -147,10 +148,10 @@ public class A_Star {
// estimated value
// given by the heuristic function to reach the destination point from the current point.
PriorityQueue<PathAndDistance> queue =
new PriorityQueue<>(Comparator.comparingInt(a -> (a.getDistance() + a.getEstimated())));
new PriorityQueue<>(Comparator.comparingInt(a -> (a.getDistance() + a.getEstimated())));
// dummy data to start the algorithm from the beginning point
queue.add(new PathAndDistance(0, new ArrayList<>(Arrays.asList(from)), 0));
queue.add(new PathAndDistance(0, new ArrayList<>(List.of(from)), 0));
boolean solutionFound = false;
PathAndDistance currentData = new PathAndDistance(-1, null, -1);