public class Hand {
    //石头的值为0
    public static final int HANDVALUE_SHITOU = 0;
    //剪刀的值为1
    public static final int HANDVALUE_JIANDAO = 1;
    //布的值为2
    public static final int HANDVALUE_BU = 2;
    //三种手势的实例
    public static final Hand[] hand = {
            new Hand(HANDVALUE_SHITOU),
            new Hand(HANDVALUE_JIANDAO),
            new Hand(HANDVALUE_BU)
    };
    //手势对应的字符串
    private static final String []name = {
            "石头", "剪刀", "布"
    };
    //猜拳中出的手势的值
    private int handValue;
    private Hand(int handValue) {
        this.handValue = handValue;
    }
    //根据手势的值获取对应的实例
    public static Hand getHand(int handValue) {
        return hand[handValue];
    }
    //如果this胜了h返回true
    public boolean isStrongerThan(Hand h) {
        return fight(h)==1;
    }
    //如果this输了h返回true
    public boolean isWeakerThan(Hand h) {
        return fight(h)==-1;
    }
    //实际用来判断胜负的方法：平0分，胜1分，输-1分
    private int fight(Hand h) {
        if (this == h) {
            return 0;
        } else if ((this.handValue+1)%3 == h.handValue) {
            return 1;
        } else {
            return -1;
        }
    }
    public String toString() {
        return name[handValue];
    }
}

public interface Strategy {
    /**
     * 获取下一局要出的手势
     */
    public abstract Hand nextHand();
    /**
     * 学习上一局的手势是否获胜了，为下一次出什么手势提供依据
     * @param win 上一局是否获胜
     */
    public abstract void study(boolean win);
}

/**
 * 该类的猜拳策略有些笨。如果上一局的手势获胜了，则下一局的手势就与上局相同；如果上一局的手势输了，则下一局就随机出手势。
 */
public class WinningStrategy implements Strategy{
    private Random random;
    //保存了上一局猜拳的输赢结果
    private boolean won = false;
    //上一局出的手势
    private Hand prevHand;
    public WinningStrategy(int seed) {
        random = new Random(seed);
    }
    @Override
    public Hand nextHand() {
        if (!won) {
            prevHand = Hand.getHand(random.nextInt(3));
        }
        return prevHand;
    }
    @Override
    public void study(boolean win) {
        won = win;
    }
}

public class ProbStrategy implements Strategy{
    private Random random;
    private int prevHandValue = 0;
    private int currentHandValue = 0;
    /**
     * history[上一局出的手势][这一局所出的手势]
     * 这个表达式的值越大，表示过去的胜率越高。下面稍微详细讲解下：
     * 假设我们上一局出的是石头。
     * history[0][0]两局分别出石头、石头时胜了的次数
     * history[0][1]两局分别出石头、剪刀时胜了的次数
     * history[0][2]两局分别出石头、布时胜了的次数
     */
    private int[][] history = {
            {1, 1, 1, },
            {1, 1, 1, },
            {1, 1, 1, },
    };
    public ProbStrategy(int seed) {
        random = new Random(seed);
    }
    /**
     * 那么，我们就可以根据 history[0][0]、history[0][1]、history[0][2]这3个表达式的值从概率上计算出下一局出什么。
     * 简而言之，就是先计算3个表达式的值的和 (getSum方法)，然后再从0与这个和之间取一个随机数，并据此决定下一局应该出什么( nextHand方法)。
     * 例如，如果
     * history[0][0]是3
     * history[0][1]是5
     * history[0][2]是7
     * 那么，下一局出什么就会以石头、剪刀和布的比率为3:5:7来决定。然后在0至15（不含15，15是3+5+7的和)之间取一个随机数。
     */
    @Override
    public Hand nextHand() {
        int bet = random.nextInt(getSum(currentHandValue));
        int handvalue = 0;
        if (bet < history[currentHandValue][0]) {
            handvalue = 0;
        } else if (bet < history[currentHandValue][0] + history[currentHandValue][1]) {
            handvalue = 1;
        } else {
            handvalue = 2;
        }
        prevHandValue = currentHandValue;
        currentHandValue = handvalue;
        return Hand.getHand(handvalue);
    }
    /**
     * study方法会根据nextHand方法返回的手势的胜负结果来更新history字段中的值。
     * @param win 上一局是否获胜
     */
    @Override
    public void study(boolean win) {
        if (win) {
            history[prevHandValue][currentHandValue]++;
        } else {
            history[prevHandValue][(currentHandValue+1)%3]++;
            history[prevHandValue][(currentHandValue+2)%3]++;
        }
    }
    private int getSum(int hv) {
        int sum = 0;
        for (int i = 0; i < 3; i++) {
            sum += history[hv][i];
        }
        return sum;
    }
}

public class Main {
    public static void main(String[] args) {
        if (args.length != 2) {
            System.out.println("Usage: java Main randomseed1 randomseed2");
            System.out.println("Example: java Main 314 15");
            System.exit(0);
        }
        int seed1 = Integer.parseInt(args[0]);
        int seed2 = Integer.parseInt(args[1]);
        Player player1 = new Player("Taro", new WinningStrategy(seed1));
        Player player2 = new Player("Hana", new ProbStrategy(seed2));
        for (int i = 0; i < 10000; i++) {
            Hand nextHand1 = player1.nextHand();
            Hand nextHand2 = player2.nextHand();
            if (nextHand1.isStrongerThan(nextHand2)) {
                System.out.println("Winner:" + player1);
                player1.win();
                player2.lose();
            } else if (nextHand2.isStrongerThan(nextHand1)) {
                System.out.println("Winner:" + player2);
                player1.lose();
                player2.win();
            } else {
                System.out.println("Even...");
                player1.even();
                player2.even();
            }
        }
        System.out.println("Total result:");
        System.out.println(player1.toString());
        System.out.println(player2.toString());
    }
}