package util.graph;

import java.util.HashSet;
import java.util.PriorityQueue;
import java.util.Set;

public class DynDjikstra {
    public static State FindShortest(Node start, Node target) {
        PriorityQueue<Node> openSet = new PriorityQueue<>();
        Set<Node> closedSet = new HashSet<>();
        openSet.add(start);
        while (!openSet.isEmpty()) {
            Node current = openSet.poll();
            for (Edge edge : current.edges) {
                Node end = edge.target;
                if (closedSet.contains(end)) {
                    continue;
                }
                State newState = edge.travel(current.last);
                //if (end.equals(target)) {
                    //return newState;
                //}
                if (openSet.contains(end)) {
                    if (end.last.compareTo(newState)>0) {
                        end.last = newState;
                    }
                } else {
                    openSet.add(end);
                    end.last = newState;
                }
            }
            closedSet.add(current);
            if (closedSet.contains(target)) {
                return target.last;
            }
        }

        return target.last;
    }
}

import java.io.BufferedReader;
import java.io.FileOutputStream;
import java.io.FileReader;

@SuppressWarnings("CallToThreadDumpStack")
public class Utils
{
    private static FileOutputStream outStream;
    private static BufferedReader reader;
    private static boolean debug = false;

    public static void openOutFile(String str, boolean debug)
    {
        Utils.debug = debug;
        try { outStream = new FileOutputStream(str, false); }
	catch (Exception e) { e.printStackTrace(); }
    }

    public static void openInFile(String str)
    {
        try { reader = new BufferedReader(new FileReader(str)); }
	catch (Exception e) { e.printStackTrace(); }
    }

    public static void closeOutFile()
    {
        try { outStream.close(); }
	catch (Exception e) { e.printStackTrace(); }
    }

    public static void closeInFile()
    {
        try { outStream.close(); }
	catch (Exception e) { e.printStackTrace(); }
    }

    public static String readFromFile()
    {
        try { return reader.readLine(); }
        catch (Exception e) { e.printStackTrace(); }
        return null; // shouldn't get here
    }
    public static void writeToFile(String str)
    {
        if (debug) System.out.println(str);
        try
        {
            for(int k=0; k<str.length(); k++)
            {
                outStream.write(str.charAt(k));
            }
            outStream.write(13);
            outStream.write(10);
        }
	catch (Exception e)
            { e.printStackTrace(); }
    }

}
