#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
using mint = atcoder::modint998244353;

// combination MOD
const int MOD=998244353;
const int MAX_N=2e6;
vector<ll> fac(MAX_N+1,1);
vector<ll> finv(MAX_N+1,1);
vector<ll> inv(MAX_N+1,1);
void comb_setup(){
	for(int i=2;i<=MAX_N;i++){
		fac.at(i)=(fac.at(i-1)*i)%MOD;
		inv.at(i)=MOD-(inv.at(MOD%i)*(MOD/i))%MOD;
		finv.at(i)=(finv.at(i-1)*inv.at(i))%MOD;
	}
}
ll comb(int n,int k){
	if(n<k) return 0;
	return fac.at(n)*(finv.at(n-k)*finv.at(k)%MOD)%MOD;
}
mint calc(int n,int k){
	return comb(n+k-2,n-1)-comb(n+k-2,n);
}

int main(){
	comb_setup();
	int n;
	cin>>n;
	vector<int> a(n);
	rep(i,n) cin>>a.at(i);
	mint ans=0;
	rep(i,n) ans+=calc(n,n-i)*a.at(i);
	cout<<ans.val()<<endl;
}