#include <iostream>
#include <unordered_map>
using namespace std;
typedef long long int64;
int64 fib[80 + 1] = {0, 1, 1};
unordered_map<int,unordered_map<int64, int>> memo;
int64 n, m;
int solve(int i, int64 k, int d)
{
    if(memo.find(i) != memo.end() && memo[i].find(k) != memo[i].end())
        return memo[i][k];
    if(k == m)
        return memo[i][k] = d;
    if(i > n || k < m)
        return memo[i][k] = -1;
    int res1 = solve(i + 1, k, d);
    int res2 = solve(i + 1, k - fib[i], d + 1);
    if(res1 == -1)
        return memo[i][k] = res2;
    if(res2 == -1)
        return memo[i][k] = res1;
    return memo[i][k] = (res1 < res2) ? res1 : res2;
}
int solve2(int i, int64 k, int d)
{
    int j = i;
    while(j >= 1 && k - fib[j] < m)
        j--;
    if(j < 1)
        return -1;
    if(k - fib[j] == m)
        return d + 1;
    int res1 = -1;
    int res2 = -1;
    res1 = solve2(j - 1, k - fib[j], d + 1);
    //res2 = solve2(j - 2, k - fib[j - 1], d + 1);
    if(res1 == -1)
        return res2;
    if(res2 == -1)
        return res1;
    return (res1 < res2) ? res1 : res2;
}
int main(void)
{
    cin >> n >> m;
    for(int i = 3; i <= n; i++)
        fib[i] = fib[i - 1] + fib[i - 2];
    if(fib[n] == m)
    {
        cout << 0 << endl;
        return 0;
    }
    cout << solve2(n - 2, fib[n], 0) << endl;
    return 0;
}