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;
    }
}

/**
 * Copyright 2012 Christopher Schmitz. All Rights Reserved.
 */

package com.isotopeent.codejam.lib;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;


public class InputReader<T> extends BufferedReader {

	private final InputConverter<T> converter;

	public InputReader(File file, InputConverter<T> converter) throws FileNotFoundException {
		super(new FileReader(file));
		this.converter = converter;
	}

	public T readInput() {
		String data;
		try {
			do {
				data = readLine();
				if (data == null) {
					return null;
				}
			} while (converter.readLine(data));
		} catch (IOException e) {
			// do nothing
		}
		return converter.generateObject();
	}

}
