#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <chrono>
#include <cmath>
#include <cstdint>
#include <cstring>
#include <ctime>
#include <deque>
#include <iomanip>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
template <typename T>
struct DSU {
  std::vector<T> f, siz;
  DSU(int n) : f(n), siz(n, 1) { std::iota(f.begin(), f.end(), 0); }
  T leader(T x) {
    while (x != f[x]) x = f[x] = f[f[x]];
    return x;
  }
  bool same(T x, T y) { return leader(x) == leader(y); }
  bool merge(T x, T y) {
    x = leader(x);
    y = leader(y);
    if (x == y) return false;
    siz[x] += siz[y];
    f[y] = x;
    return true;
  }
  T size(int x) { return siz[leader(x)]; }
};

std::pair<std::vector<long long>, std::vector<int>> get_prime_factor_with_kinds(
    long long n) {
  std::vector<long long> prime_factors;
  std::vector<int> cnt;  // number of i_th factor
  for (long long i = 2; i <= sqrt(n); i++) {
    if (n % i == 0) {
      prime_factors.push_back(i);
      cnt.push_back(0);
      while (n % i == 0) n /= i, cnt[(int)prime_factors.size() - 1]++;
    }
  }
  if (n > 1) prime_factors.push_back(n), cnt.push_back(1);
  assert(prime_factors.size() == cnt.size());
  return {prime_factors, cnt};
}

void solve() {
  int a, b, c, d;
  std::cin >> a >> b >> c >> d;
  int ans1 = a + b + c + d;
  int ans2 = std::max({a, b, c, d}) * 3;
  std::cout << std::max(ans1, ans2) << '\n';  
}
int main() {
  std::cin.tie(nullptr);
  std::ios::sync_with_stdio(false);
  int t = 1;
  // std::cin >> t;
  while (t--) solve();
  // solve();
  return 0;
}