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#include <iostream>
#include <string>
using namespace std;

int main()
{
	string napis;
	cin >> napis;

	unsigned long long fib[2] = { 0ULL, 1ULL };

	while(napis[0] == '0')
		napis.erase(napis.begin());

	int len = napis.length();

	unsigned long long currNum = 0ULL;

	unsigned long long k = 2ULL;

	while (k <= 1.e+100)
	{
		currNum = fib[0] + fib[1];
		string currStr = to_string(currNum);
		int currLen = currStr.length();
		if (currLen >= len && currStr.substr(currLen - len, len) == napis)
		{
			cout << k << endl;
			return 0;
		}
		fib[0] = fib[1];
		fib[1] = currNum;

		k++;
	}

	cout << "NIE" << endl; 
	return 0;
}