flavius.java

Ulm大学2005-2006年竞赛题

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

public class flavius {
	public static void main(String [] args) throws Exception {
		int n;
		Scanner in = new Scanner(new File("flavius.in"));
		while((n = in.nextInt()) != 0) {
			int a = in.nextInt();
			int b = in.nextInt();
			long x = 0;
			HashMap<Integer,Integer> visit = new HashMap<Integer,Integer>();
			int c = 0;
			while(true) {
				++c;
				if (visit.get((int)x) != null) {
					int t = visit.get((int)x);
					System.out.println(n-(c-t));
					break;
				}
				visit.put((int)x,c);
				x = ((((x*x)%n)*a)%n+b)%n;
			}
		}
	}
}