#include <bits/stdc++.h>
using namespace std;
const double PI = acos(-1);
const int INF = 1000 * 1000 * 1000 + 7;
const long long LINF = INF * (long long)INF;
const int MAX = 1000 * 100 + 47;
long long A[MAX];
long long P[MAX];
long long Q[MAX];
long long R[MAX];
int main() {
  int n;
  long long p, q, r;
  cin >> n >> p >> q >> r;
  for (int i = (0); i < (n); i++) cin >> A[i];
  for (int i = (0); i < (n); i++) {
    P[i] = p * A[i];
    if (i) P[i] = max(P[i], P[i - 1]);
    Q[i] = P[i] + q * A[i];
    if (i) Q[i] = max(Q[i], Q[i - 1]);
    R[i] = Q[i] + r * A[i];
    if (i) R[i] = max(R[i], R[i - 1]);
  }
  cout << R[n - 1] << endl;
  return 0;
}
