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#include <iostream>
#include <algorithm>
using namespace std;
int main()
{
    ios_base::sync_with_stdio(0);
    unsigned long long int n;
    cin >> n;
    if (n<=1)
    {
        cout << n;
        return 0;
    }
    unsigned long long a=1, b=1, c, mod=10;
    while (mod<=n)
        mod*=10;
    //cout << mod << " ";
    for (int i=3; i<=10000000; i++)
    {
        c=a+b;
        c%=mod;
        //cout << c << "\n";
        if (c==n)
        {
            cout << i << "\n";
            return 0;
        }
        a=b;
        b=c;
    }
    cout << "NIE";
    return 0;
}