#include <iostream>
using namespace std;

int main() {
	long long fibo[80];
	fibo[0] = 1;
	fibo[1] = 1;
	for(int i = 2; i < 80; i++){
		fibo[i] = fibo[i-1] + fibo[i-2];
	}
	
	int n;
	long long m;
	cin >> n >> m;
	if(fibo[n-1] < m){
		cout << -1 << endl;
	}else if(fibo[n-1] == m){
		cout << 0 << endl;
	}else{
		int sum = 0;
		m = fibo[n-1] - m;
		while(m > 0){
			for(int i = 79; i > 0; i--){
				if(m > fibo[i]){
					sum++;
					m -= fibo[i];
				}else if(m == fibo[i]){
					sum++;
					m = 0;
					cout << sum << endl;
					break;
				}
			}
		}
	}
	
	return 0;
}