#include<bits/stdc++.h>
using namespace std;

#define pb emplace_back
#define mp make_pair
 
using ll = long long;
using pii = pair<int,int>;
 
constexpr int mod = 998244353;
constexpr int inf = 0x3f3f3f3f;
constexpr int N = 2e5 + 10;

int n, a[N];
ll b[N];

void _main(){
  cin >> n;
  for(int i=1; i<=n; ++i) cin >> a[i];
  if(n == 1){
    b[1] = 1;
  } else if(n == 2){
    b[1] = b[2] = 3;
  } else {
    ll x = 1, y = 4, z = 5;
    for(int i=4; i<=n; ++i){
      x = x * 2 % mod;
      y = (y * 2 + x) % mod;
      z = (z * 2 + x) % mod;
    }
    for(int i=1; i<=n; ++i){
      b[i] = (y * i + z - i * i % mod * x) % mod;
      if(b[i] < 0)  b[i] += mod;
    }
  }
  ll ans = 0;
  for(int i=1; i<=n; ++i) ans += a[i] * b[i] % mod;
  cout << ans % mod << '\n';
}

int main(){
  ios::sync_with_stdio(0);
  cin.tie(0); cout.tie(0);
  _main();
  return 0;
}