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//Autor: Mateusz Wasylkiewicz
//Zawody: Potyczki Algorytmiczne 2015
//Strona: http://potyczki.mimuw.edu.pl/
//Zadanie: Fibonacci, runda 2B
//Czas: Theta(10^n)
#include <bits/stdc++.h>
using namespace std;

typedef long long LL;
#define FOR(x, a, b) for (LL x = (a); x <= (b); x++)
#define REP(x, n) for (LL x = 0; x < (n); x++)
#define SIZE(x) LL((x).size())

const LL MAX = 90;
LL fib[MAX];

void wczytaj_dane(const string& s, LL& n, LL& c)
{
	n = SIZE(s);
	stringstream ss(s);
	ss >> c;
}

void wypelnij_fib()
{
	REP(i, 2)
		fib[i] = i;
	FOR(i, 2, MAX - 1)
		fib[i] = fib[i - 1] + fib[i - 2];
}

LL potega(LL a, LL b)
{
	LL w = 1;
	while (b--)
		w *= a;
	return w;
}

void rozwiaz(LL n, LL c)
{
	LL pot = potega(10, n), a[2] = {0, 1}, g = max(1000LL, (3 * pot) / 2 + 4 * MAX);
	REP(k, g)
	{
		if (a[0] == c && (k >= MAX || fib[k] >= pot / 10))
		{
			cout << k << '\n';
			return;
		}
		LL pom = (a[0] + a[1]) % pot;
		a[0] = a[1];
		a[1] = pom;
	}
	cout << "NIE\n";
}

void zrob_test()
{
	string s;
	LL n, c;
	cin >> s;
	wczytaj_dane(s, n, c);
	wypelnij_fib();
	rozwiaz(n, c);
}

int main()
{
	//ios_base::sync_with_stdio(false);
	//cin.tie(NULL);
	zrob_test();
	return 0;
}