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;
    }
}

package codejam;

import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;

public class Util {
	public int testcases;
	BufferedReader br;
	public Util(String file) throws FileNotFoundException {
	      FileInputStream fstream = new FileInputStream(file);
	      Reader r = new BufferedReader(new InputStreamReader(fstream));
	      //while(st.nextToken())
	      DataInputStream in = new DataInputStream(fstream);
	      br = new BufferedReader(new InputStreamReader(in));
	      String str="";
	      try {
	    	  str = br.readLine();
	      } catch (IOException e) {
	    	  e.printStackTrace();
	      }
	      testcases = Integer.parseInt(str);
	}
	
	public String nextLine() throws IOException {
		return br.readLine();
	}
	
	protected void finalize() {
		try {br.close();}catch(IOException e){}
	}
}
