四色定理Java实现美图

我试图为每个状态指定一种颜色,以便没有两个相邻的状态共享相同的颜色(http://en.wikipedia.org/wiki/Four_color_theorem).程序将输出每个状态及其颜色.

我正在读取一个文本文件,其格式为48个状态(2个未连接):

al,fl,ms,tn,ga
ar,la,tx,ok,mo,tn,ms
az,ca,nv,ut,nm
ca,az,nv,or
co,wy,ut,nm,ok,ks,ne
...

例:

阿拉巴马州接触佛罗里达州,密西西比州,田纳西州和佐治亚州.

阿肯色州接触路易斯安那州,德克萨斯州等.

到目前为止这是我的代码:

MapColor.java    

import java.io.*;
import java.util.*;

public class MapColor {

    public static void main(String[] args) throws IOException {

        ArrayList  statestemp = new ArrayList  ();
        ArrayList  states = new ArrayList  ();

        // read in each line
        BufferedReader reader = new BufferedReader(new FileReader("usa.txt"));
        String line = null;
        while ((line = reader.readLine()) != null) {
            statestemp.add(line);
        }
        reader.close();

        // create all state objects and adjacencies
        for (int i = 0; i < statestemp.size(); i++) {
            State st = new State();
            String[] str = statestemp.get(i).split(",");
            st.setName(str[0]);
            for (int j = 1; j < str.length; j++) {
                st.addAdj(str[j]);
            }
            states.add(st);
        }

        // set colors


        // print out states and adjacencies
        for (State s : states) {
            System.out.println("Name: " + s.getName());
            System.out.println("Color: " + s.getColor());
            System.out.print("Adj: ");
            s.getAdj();
            System.out.println();
            System.out.println();
        }

    }
}

和

State.java

import java.util.ArrayList;

public class State {

    public String n = null;
    public int c = 0;
    public ArrayList  adj = new ArrayList  ();

    public String getName() {
        return n;
    }
    public void setName(String name) {
        this.n = name;
    }
    public int getColor() {
        return c;
    }
    public void setColor(int color) {
        this.c = color;
    }
    public void addAdj(String s) {
        this.adj.add(s);
    }
    public ArrayList  getAdj() {
        return this.adj;
    }
}

我正处于开始分配颜色的地步,但我不确定如何进行比较.

任何建议,将不胜感激!