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#include <iostream>
#include <cmath>
#include <string>

using namespace std;

long long a = 0, b = 1, c = 1, sum;

long long cnt = 2; // 1, 1 już są

string tail, str_c;
long long modulo;
int padding;

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

    cin >> tail;
    modulo = static_cast<long long>(pow(10, tail.length()) + 0.5);

    //clog << modulo << endl;

    while (true)
    {
        sum = (b + c) % modulo;
        a = b;
        b = c;
        c = sum;
        ++cnt;
        //cout << c << endl;
        if (cnt > 10 && a == 2 && b == 3 && c == 5)
        {
            cout << "NIE\n";
            //cout << c;
            break;
        }

        str_c = to_string(c);
        //clog << str_c << endl;
        padding = tail.length() - str_c.length();
        if (padding != 0) str_c = string(padding, '0') + str_c;
        //clog << "padding " << padding << endl;
        //clog << str_c << endl;


        if (str_c == tail)
        {
            cout << cnt << endl;
            break;
        }
    }

    return 0;
}