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import java.io.InputStream;
import java.io.PrintStream;
import java.math.BigInteger;
import java.util.*;

public class fib {
    public static void main(String[] args) {
        InputStream in = System.in;
        PrintStream out = System.out;
        calculate(in, out);
    }

    public static int calculate(InputStream in, PrintStream out) {
        /** Read input and init tables */

        Scanner scanner = new Scanner(in);
        String ending = scanner.next();
        scanner.close();

        long found = findFn(lastChars(ending, 2), 1000);
        if (found == -1) {
            out.println("NIE");
            return 0;
        }

        found = findFn(lastChars(ending, 3), 10000);
        if (found == -1) {
            out.println("NIE");
            return 0;
        }

        found = findFn(lastChars(ending, 5), 100000);
        if (found == -1) {
            out.println("NIE");
        } else {
            out.println(found);
        }

        return 0;
    }

    private static String lastChars(String ending, int size) {
        if (size > 0 && ending.length() > size) {
            return ending.substring(ending.length() - size);
        } else {
            return ending;
        }
    }
    private static long findFn(String ending, int limit) {
        BigInteger tail = new BigInteger(ending);
        BigInteger tailCut = BigInteger.TEN.pow(ending.length());
        BigInteger tfn0 = BigInteger.ZERO;
        BigInteger tfn1 = BigInteger.ONE;
        BigInteger tfn = null;
        long n = 1;

        while (n < limit || limit == -1) {
            n++;
            tfn = tfn0.add(tfn1).mod(tailCut);
            tfn0 = tfn1;
            tfn1 = tfn;

            if (tfn.compareTo(tail) == 0) {
                String v = tfn.toString();
                if (pad(v, ending.length()).equals(ending)) {
                    return n;
                }
            }
        }
        return -1;
    }

    private static String pad(String v, int length) {
        while (v.length() < length) {
            v = "0" + v;
        }
        return v;
    }

}