#include <bits/stdc++.h>
using namespace std;

int main() {
	set<pair<int64_t, int64_t>> s;
	{
		pair<int64_t, int64_t> p;
		cin >> p.first >> p.second;
		s.insert(p);
	}
	for (int64_t ans = 0; ans < 50; ans++) {
		set<pair<int64_t, int64_t>> next;
		for (auto p : s) {
			if (p.first == p.second) {
				cerr << p.first << ' ' << p.second << endl;
				cout << ans << endl;
				return 0;
			}
			next.insert({p.second, p.first});
			next.insert({p.first + p.second, p.first - p.second});
		}
		swap(s, next);
	}
	cout << -1 << endl;
	return 0;
}