#include <iostream>
#include <algorithm>
#include <vector>
#include <string>

constexpr int INF = 1 << 25;

int calc(int n, const std::vector<int>& ds) {
    std::vector<int> dp(n + 1, INF);
    dp[0] = 0;
    for (int x = 1; x <= n; ++x) {
        for (auto d : ds) {
            if (x - d < 0) continue;
            dp[x] = std::min(dp[x], dp[x - d] + 1);
        }
    }
    return dp[n];
}

void solve() {
    std::vector<int> vs(4);
    for (auto& v : vs) std::cin >> v;

    std::vector<int> ds(3);
    int ans = INF;

    for (ds[0] = 1; ds[0] <= 30; ++ds[0]) {
        for (ds[1] = 1; ds[1] < ds[0]; ++ds[1]) {
            for (ds[2] = 1; ds[2] < ds[1]; ++ds[2]) {
                int sum = 0;
                for (auto v : vs) sum += calc(v, ds);
                ans = std::min(ans, sum);
            }
        }
    }

    std::cout << ans << "\n";
}

int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    solve();

    return 0;
}