func_code_string: #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;   }   