Game of Taking Stones (大数 + 威佐夫博弈 java写的)

C - Game of Taking Stones

 

import java.math.BigDecimal;
import java.util.Scanner;

public class Main
{

    public static void main(String[] args)
    {
        BigDecimal TWO = BigDecimal.valueOf(2);
        BigDecimal FIVE = BigDecimal.valueOf(5);

        BigDecimal EPS = new BigDecimal(
                "-0.0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001");

        BigDecimal l = new BigDecimal("2.2360679774997"), r = new BigDecimal("2.2360679774998");
        BigDecimal m = null;

        while (l.subtract(r).compareTo(EPS) < 0)
        {
            m = l.add(r).divide(TWO);
            if (m.multiply(m).subtract(FIVE).abs().compareTo(EPS.abs()) < 0)
                break;
            if (m.multiply(m).subtract(FIVE).compareTo(EPS) < 0)
                l = m;
            else
                r = m;
        }


        BigDecimal GOLD = m.add(BigDecimal.ONE).divide(TWO);

        Scanner sc = new Scanner(System.in);
        while (sc.hasNext())
        {
            BigDecimal a = sc.nextBigDecimal(), b = sc.nextBigDecimal();
            if (a.compareTo(b) > 0)
            {
                BigDecimal t = a;
                a = b;
                b = t;
            }

            BigDecimal c = b.subtract(a).setScale(0, BigDecimal.ROUND_FLOOR).multiply(GOLD);
            c = c.setScale(0, BigDecimal.ROUND_FLOOR);
            if (a.equals(c))
                System.out.println("0");
            else
                System.out.println("1");
        }
        sc.close();
    }
}