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//	Michał Wiatrowski

#include <iostream>
#include <vector>
#include <stack>
#include <string>
#include <queue>

using namespace std;

typedef unsigned long long uint64;
typedef long long int64;


int64 A = 0x7fffffffffffff01;
int64 B = 0x7fffffffffffff02;
int64 M = 0x7fffffffffffff03;

// For simplicity it is assumed x, y, and m are all positive.
int64 addmod(int64 x, int64 y, int64 m) {
 	x %= m;
 	y %= m;
 	int64 sum = x - m + y; // -m <= sum < m-1
	return sum < 0 ? sum + m : sum;
}

int64 timesmod(int64 x, int64 y, int64 m) {
	x %= m;
	y %= m;
	int64 a = x < y ? x : y; // min
	int64 b = x < y ? y : x; // max
	int64 product = 0;
	for (; a != 0; a >>= 1, b = addmod(b,b,m) )
		if (a&1) product = addmod(product,b,m);
	return product;
}





uint64 fibonacci(uint64 index, uint64 modulo) {
	if (index == 0)
		return 0;
	if (index == 1)
		return 1;

	index--;

	uint64 a = 1, b = 1, c = 1, d = 0;
	stack<char> s;
	
	while (index > 1) {
		if (index % 2 == 0) {
			index /= 2;
			s.push('d');
		} else {
			index -= 1;
			s.push('m');
		}
	}

	while (!s.empty()) {
		uint64 aa = a, bb = b, cc = c, dd = d;

		char cmd = s.top();
		s.pop();

		if (cmd == 'd') {
			a = (timesmod(aa, aa, modulo) + timesmod(bb, cc, modulo)) % modulo;
			b = (timesmod(aa, bb, modulo) + timesmod(bb, dd, modulo)) % modulo;
			c = (timesmod(aa, cc, modulo) + timesmod(cc, dd, modulo)) % modulo;
			d = (timesmod(cc, bb, modulo) + timesmod(dd, dd, modulo)) % modulo;
		} else {
			a = (aa + bb) % modulo;
			b = aa;
			c = (cc + dd) % modulo;
			d = cc;
		}
	}

	return (c + d) % modulo;
}


int main() {
	ios_base::sync_with_stdio(false);

	string napis;
	cin >> napis;

	uint64 liczba = 0;
	uint64 obciecie = 1;
	for (char c : napis) {
		liczba *= 10;
		liczba += (c - '0');
		obciecie *= 10;
	}

	int wykladnik = napis.size();
	uint64 mod = 1;
	for (int i = 0; i < wykladnik; ++i)
		mod *= 10;

	if (liczba == 0 && wykladnik == 1) {
		cout << 0 << endl;
		return 0;
	}

	uint64 wynik = 0;
	queue<pair<uint64, uint64>> stany;

	for (int i = 0; i < 60; ++i) {
		if (fibonacci(i, 10) == liczba % 10)
			stany.push(make_pair(i, 10));
	}

	while (!stany.empty()) {
		uint64 index = stany.front().first;
		uint64 modulo = stany.front().second;
		stany.pop();

		if (wykladnik == 1) {
			if (fibonacci(index, mod) == liczba % 10) {
				wynik = index;
				break;
			}
		}

		uint64 duzyCykl = modulo * 15;
		uint64 malyCykl = modulo * 15 / 10;
		if (modulo == 10) {
			malyCykl = 60;
			duzyCykl = 300;
		}
		if (modulo == 100) {
			malyCykl = 300;
		}

		for (uint64 i = 0; i < (duzyCykl / malyCykl); ++i) {
			if (i * malyCykl > 1500000000000000000 - index)
				continue;

			uint64 kandytat = index + i * malyCykl;
			uint64 noweModulo = modulo * 10;

			if (fibonacci(kandytat, noweModulo) == liczba % noweModulo) {
				if (noweModulo == mod) {
					wynik = kandytat;
					break;
				} else {
					stany.push(make_pair(kandytat, noweModulo));
				}
			}
		}
	}

	if (wynik != 0)
		cout << wynik;
	else
		cout << "NIE" << endl;

	return 0;
}