#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i, n) for(ll i = 0, i##_len = (n); i < i##_len; i++)
#define reps(i, s, n) for(ll i = (s), i##_len = (n); i < i##_len; i++)
#define rrep(i, n) for(ll i = (n) - 1; i >= 0; i--)
#define rreps(i, e, n) for(ll i = (n) - 1; i >= (e); i--)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) ((ll)(x).size())
#define len(x) ((ll)(x).length())
#define endl "\n"

ll is_fib(const vector<ll> &fib, ll v) {
    auto it = lower_bound(all(fib), v);
    if ((it == fib.end()) || (v != *it)) return -1;
    return (it - fib.begin());
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    // ifstream in("input.txt");
    // cin.rdbuf(in.rdbuf());
    vector<ll> fib(80);
    fib[0] = 1; fib[1] = 1;
    reps(i, 2, sz(fib)) {
        fib[i] = fib[i - 1] + fib[i - 2];
    }
    vector<ll> a(5);
    rep(i, 5) cin >> a[i];
    reverse(all(a));
    ll idx = is_fib(fib, a[0]);
    if (idx == -1) {
        cout << 0 << endl;
        return 0;
    }
    ll st = 1;
    if ((a[0] == 1) && (a[1] == 1)) {
        st++;
    }
    else if (a[0] == 1) {
        idx++;
    }
    rep(i, 5 - st) {
        if (fib[idx + st + i] != a[i + st]) {
            cout << (i + st) << endl;
            return 0;
        }
    }
    cout << 5 << endl;
    return 0;
}