import java.awt.*;
import java.applet.*;
import java.awt.event.*;

public class Renju extends Applet implements Runnable,MouseListener {
	Phase current=new Phase();
	Image offscreen;
	
	public void init() {
		setBackground(new Color(0xCC,0x99,0x33));
		current.resize(this);
		addMouseListener(this);
	}


	public void start() {
		current=new Phase();
	}
	
	public void update(Graphics g) {
		paint(g);
	}
	
	public void paint(Graphics g) {
		if (offscreen==null)
			offscreen=createImage(getSize().width,getSize().height);
		Graphics og=offscreen.getGraphics();
		current.paint(og);
		g.drawImage(offscreen,0,0,this);
	}
	
	public void mouseClicked(MouseEvent e) {
		if (current.checkmate)
			start();
		else if (current.turn)
			current=current.mouse(e.getX(),e.getY());
		repaint();
		new Thread(this).start();
	}
	public void mouseEntered(MouseEvent e) {}
	public void mouseExited(MouseEvent e) {}
	public void mousePressed(MouseEvent e) {}
	public void mouseReleased(MouseEvent e) {}
		
	public void run() {
		try {
			Thread.sleep(1000);
		} catch (InterruptedException e) {
		}
		if (!current.turn)
			current=current.put();
		repaint();
	}
	
}

class Phase {
	static int size=19, pitch=15;
	static int[][] direction={{1,0},{1,1},{0,1},{-1,1},{-1,0},{-1,-1},{0,-1},{1,-1}};
	static int[][] valuetable={{0,1,4,9,20},{2,3,5,10,21},{6,7,8,11,22},{12,13,14,15,23},{16,17,18,19,24}};
	boolean[][] color=new boolean[size][size];
	boolean[][] exist=new boolean[size][size];
	boolean turn;
	boolean brandnew=false,checkmate;
	int[] point=new int[4];
	
	Phase() {
		for (int x=0; x<size; x++) for (int y=0; y<size; y++) {
			exist[x][y]=false;
			color[x][y]=false;}
		turn=true;
		brandnew=true;
	}
	
	Phase(Phase p) {
		for (int x=0; x<size; x++) for (int y=0; y<size; y++) {
			exist[x][y]=p.exist[x][y];
			color[x][y]=p.color[x][y];}
		turn=p.turn;
	}
	
	int chain (int x, int y) {
		return chain(x,y,turn);
	}
	
	int chain (int x,int y,boolean t) {
		int[] chains=new int[8];
		for (int dir=0; dir<8; dir++) {
			for (int step=1; true; step++) {
				int xx=x+step*direction[dir][0];
				int yy=y+step*direction[dir][1];
				if (xx<0 || xx>=size || yy<0 || yy>=size || ! exist[xx][yy] || color[xx][yy]!=t) {
					chains[dir]=step-1;
					break;}}}
		int largest=0;
		for (int dir=0; dir<4; dir++)
			if (chains[dir]+chains[dir+4]>largest)
				largest=chains[dir]+chains[dir+4];
		return largest;
	}
	
	void examinate (int x,int y) {
		int[] chains=new int[8];
		for (int dir=0; dir<8; dir++) {
			for (int step=1; true; step++) {
				int xx=x+step*direction[dir][0];
				int yy=y+step*direction[dir][1];
				if (xx<0 || xx>=size || yy<0 || yy>=size || ! exist[xx][yy] || color[xx][yy]==turn) {
					chains[dir]=step-1;
					break;}}}
		int largest=0;
		for (int dir=0; dir<4; dir++)
			if (chains[dir]+chains[dir+4]>3) {
				largest=chains[dir]+chains[dir+4];
				point[0]=x+chains[dir]*direction[dir][0];
				point[1]=y+chains[dir]*direction[dir][1];
				point[2]=x+chains[dir+4]*direction[dir+4][0];
				point[3]=y+chains[dir+4]*direction[dir+4][1];
			}
	}
	
	synchronized Phase put (int x,int y) {
		if (exist[x][y] || checkmate) return this;
		Phase next=new Phase(this);
		next.exist[x][y]=true;
		next.color[x][y]=turn;
		next.turn=!turn;
		if (chain(x,y)>3) {
			next.checkmate=true;
			next.examinate(x,y);}
		return next;
	}
	
	Phase mouse (int x,int y) {
		return put((x-pitch/2)/pitch,(y-pitch/2)/pitch);
	}
	
	Phase put () {
		int optimumX=size/2,optimumY=size/2;
		for (int x=0; x<size; x++) for (int y=0; y<size; y++)
			if (value(x,y)>value(optimumX,optimumY)) {
				optimumX=x;
				optimumY=y;}
		return put(optimumX,optimumY);
	}
	
	int value(int x,int y) {
		if (exist[x][y]) return 0;
		try {
			return valuetable[chain(x,y,!turn)][chain(x,y,turn)];
		} catch (ArrayIndexOutOfBoundsException e) {
			return 25;
		}
	}
	
	void resize(Applet a) {
		a.resize((size+1)*pitch,(size+1)*pitch);
	}
	
	void paint (Graphics g) {
		if (brandnew) {
			g.setColor(new Color(0xCC,0x99,0x33));
			g.fillRect(0,0,(size+1)*pitch,(size+1)*pitch);
			brandnew=false;}
		g.setColor(Color.darkGray);
		for (int x=0; x<size; x++)
			g.drawLine(pitch+pitch*x,pitch,pitch+pitch*x,pitch*size);
		g.setColor(Color.black);
		for (int y=0; y<size; y++)
			g.drawLine(pitch,pitch+pitch*y,pitch*size,pitch+pitch*y);
		for (int x=0; x<size; x++) for (int y=0; y<size; y++)
			if (exist[x][y] && color[x][y])
				g.fillOval(pitch/2+pitch*x+2,pitch/2+pitch*y+2,pitch-2,pitch-2);
		g.setColor(Color.white);
		for (int x=0; x<size; x++) for (int y=0; y<size; y++)
			if (exist[x][y] && !color[x][y])
				g.fillOval(pitch/2+pitch*x+2,pitch/2+pitch*y+2,pitch-2,pitch-2);
		if (checkmate) {
			g.setColor(Color.red);
			g.drawLine(pitch+pitch*point[0],pitch+pitch*point[1],pitch+pitch*point[2],pitch+pitch*point[3]);}
	}
}