poj 2427 Smith's Problem pell方程

import java.io.BufferedInputStream;

import java.math.BigInteger;

import java.util.Scanner;



public class Main {

	public static BigInteger p, q;



	public static void solve(int n) {

		BigInteger N, p1, p2, q1, q2, a0, a1, a2, g1, g2, h1, h2;

		p1 = BigInteger.ZERO;

		p2 = BigInteger.ONE;

		q1 = p2;

		q2 = p1;

		a0 = a1 = BigInteger.valueOf((long) Math.sqrt(1.0 * n));

		g1 = p1;

		h1 = p2;

		N = BigInteger.valueOf(n);

		while (true) {

			g2 = a1.multiply(h1).subtract(g1);

			h2 = N.subtract(g2.pow(2)).divide(h1);

			a2 = g2.add(a0).divide(h2);

			p = a1.multiply(p2).add(p1);

			q = a1.multiply(q2).add(q1);

			if (p.pow(2).subtract(N.multiply(q.pow(2))).compareTo(

					BigInteger.ONE) == 0) {

				return;

			}

			g1 = g2;

			h1 = h2;

			a1 = a2;

			p1 = p2;

			p2 = p;

			q1 = q2;

			q2 = q;

		}

	}



	public static void main(String[] args) {

		Scanner cin = new Scanner(new BufferedInputStream(System.in));

		int n, temp;

		while (cin.hasNext()) {

			n = cin.nextInt();

			temp = (int) Math.sqrt(n * 1.0);

			if (temp * temp == n) {

				System.out.println("No solution!");

				continue;

			}

			solve(n);

			System.out.println(p + " " + q);

		}

	}

}