/* #region Head */

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

using ll = long long;
using ull = unsigned long long;
using pll = pair<ll, ll>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vd = vector<double>;
using vvd = vector<vd>;
using vs = vector<string>;
using vvs = vector<vs>;

#define REP(i, m, n) for (ll i = (m), i##_len = (ll)(n); i < i##_len; ++(i))
#define REPM(i, m, n) for (ll i = (m), i##_max = (ll)(n); i <= i##_max; ++(i))
#define REPR(i, m, n) for (ll i = (m), i##_min = (ll)(n); i >= i##_min; --(i))
#define REPD(i, m, n, d) for (ll i = (m), i##_len = (ll)(n); i < i##_len; i += (d))
#define REPMD(i, m, n, d) for (ll i = (m), i##_max = (ll)(n); i <= i##_max; i += (d))
#define REPI(itr, ds) for (auto itr = ds.begin(); itr != ds.end(); itr++)
#define ALL(x) begin(x), end(x)
#define SIZE(x) ((ll)(x).size())

constexpr ll INF = 1'010'000'000'000'000'017LL;
constexpr ll MOD = 1'000'000'007LL; // 1e9 + 7
constexpr double EPS = 1e-12;
constexpr double PI = 3.14159265358979323846;

// vector入力
template <typename T>
istream &operator>>(istream &is, vector<T> &vec)
{
    for (T &x : vec)
        is >> x;
    return is;
}

// vector出力
template <typename T>
ostream &operator<<(ostream &os, vector<T> &vec)
{
    ll len = SIZE(vec);
    os << "{";
    for (int i = 0; i < len; i++)
        os << vec[i] << (i == len - 1 ? "" : ", ");
    os << "}";
    return os;
}

// pair入力
template <typename T, typename U>
istream &operator>>(istream &is, pair<T, U> &pair_var)
{
    is >> pair_var.first >> pair_var.second;
    return is;
}

// pair出力
template <typename T, typename U>
ostream &operator<<(ostream &os, pair<T, U> &pair_var)
{
    os << "(" << pair_var.first << ", " << pair_var.second << ")";
    return os;
}

// map出力
template <typename T, typename U>
ostream &operator<<(ostream &os, map<T, U> &map_var)
{
    os << "{";
    REPI(itr, map_var)
    {
        os << *itr;
        itr++;
        if (itr != map_var.end())
            os << ", ";
        itr--;
    }
    os << "}";
    return os;
}

// set 出力
template <typename T>
ostream &operator<<(ostream &os, set<T> &set_var)
{
    os << "{";
    REPI(itr, set_var)
    {
        os << *itr;
        itr++;
        if (itr != set_var.end())
            os << ", ";
        itr--;
    }
    os << "}";
    return os;
}

// dump
#define DUMPOUT cerr
void dump_func()
{
    DUMPOUT << endl;
}
template <class Head, class... Tail>
void dump_func(Head &&head, Tail &&... tail)
{
    DUMPOUT << head;
    if (sizeof...(Tail) > 0)
    {
        DUMPOUT << ", ";
    }
    dump_func(move(tail)...);
}

// _max の終端．
template <class Head>
ll _max(Head &&head)
{
    return head;
}
// 最大値を求める．max({}) の代わり．これにしないと vscode が壊れる．
template <class Head, class... Tail>
ll _max(Head &&head, Tail &&... tail)
{
    return max((ll)head, _max((tail)...));
}

// _min の終端．
template <class Head>
ll _min(Head &&head)
{
    return head;
}
// 最小値を求める．min({}) の代わり．これにしないと vscode が壊れる．
template <class Head, class... Tail>
ll _min(Head &&head, Tail &&... tail)
{
    return min((ll)head, _min((tail)...));
}

// chmax (更新「される」かもしれない値が前)
template <typename T, typename U, typename Comp = less<>>
bool chmax(T &xmax, const U &x, Comp comp = {})
{
    if (comp(xmax, x))
    {
        xmax = x;
        return true;
    }
    return false;
}

// chmin (更新「される」かもしれない値が前)
template <typename T, typename U, typename Comp = less<>>
bool chmin(T &xmin, const U &x, Comp comp = {})
{
    if (comp(x, xmin))
    {
        xmin = x;
        return true;
    }
    return false;
}

// container 内の最初の element のインデックスを探す
template <class Container>
ll indexof(const Container &container, const typename Container::value_type &element)
{
    auto iter = find(container.begin(), container.end(), element);
    size_t index = distance(container.begin(), iter);
    if (index == container.size())
    {
        index = -1;
    }
    return index;
}

// ローカル用
#define DEBUG_

#ifdef DEBUG_
#define DEB
#define dump(...)                                                       \
    DUMPOUT << "  " << string(#__VA_ARGS__) << ": "                     \
            << "[" << to_string(__LINE__) << ":" << __FUNCTION__ << "]" \
            << endl                                                     \
            << "    ",                                                  \
        dump_func(__VA_ARGS__)
#else
#define DEB if (false)
#define dump(...)
#endif

struct AtCoderInitialize
{
    static constexpr int IOS_PREC = 15;
    static constexpr bool AUTOFLUSH = false;

    AtCoderInitialize()
    {
        ios_base::sync_with_stdio(false);
        cin.tie(nullptr);
        cout.tie(nullptr);
        cout << fixed << setprecision(IOS_PREC);
        if (AUTOFLUSH)
            cout << unitbuf;
    }
} ATCODER_INITIALIZE;

/* #endregion */

/**
5行の入力データが与えられます。
下から数えてn行目まで、下から見て昇順で連続したフィボナッチ数列(1,1,2,3,…)の一部になっているような最大のn(1 <= n <= 5)を出力して下さい。
条件に合うnがない場合、0を出力して下さい。
詳細は入力例を見て確認して下さい。
 */
void solve()
{
    vll a(5);
    cin >> a;
    reverse(ALL(a));

    // gen fibonacci nums
    vll fibonacci;
    ll i0 = 1, i1 = 1, i2;
    fibonacci.emplace_back(i0);
    fibonacci.emplace_back(i1);
    while (i1 <= 1e15)
    {
        i2 = i0 + i1;
        fibonacci.emplace_back(i2);
        i0 = i1;
        i1 = i2;
    }

    // dump(fibonacci, a);
    ll cnt = 0;
    auto iter = lower_bound(ALL(fibonacci), a[cnt]);
    if (iter != fibonacci.end())
    {
        if ((a[0] == 1 && a[1] == 2))
            ++iter;
        while (cnt < 5)
        {
            if (*iter != a[cnt])
                break;
            ++cnt;
            ++iter;
        }
    }
    cout << cnt << endl;
}

/**
 * エントリポイント．
 * @return 0.
 */
int main()
{
    solve();
    return 0;
}