import java.math.BigInteger;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws Exception {
		Scanner sc = new Scanner(System.in);
		BigInteger n = sc.nextBigInteger();
		BigInteger b = sc.nextBigInteger();
		sc.close();

		try {
			BigInteger ans = n.modInverse(b);
			System.out.println(ans);
		} catch (Exception e) {
			System.out.println("NaN");
		}
	}
}