#include <bits/stdc++.h>   using namespace std;   int main() {     int n;     cin >> n;     int x = 0, xi = INT_MIN, q = 0;     vector<int> v;     for (int i = 0; i < n; i++) {       int y;       cin >> y;       q = x;       v.push_back(y);       xi = max(x, v[i]);       if (x != q) x = i;     }     long long ans = 0;     for (int i = 0; i < n; i++) {       int z = (abs(x - i) + i + x) * 2;       ans += (z * v[i]);     }     cout << ans;     return 0;   }   