#include<bits/stdc++.h>
// #include<atcoder/all>

using namespace std;
// using namespace atcoder;
using ll = long long;
using ull = unsigned long long;
using P = pair<int,int>;
#define rep(i,n) for(ll i = 0;i < (ll)n;i++)
#define ALL(x) (x).begin(),(x).end()
#define MOD 1000000007

const int mod = 998244353;


ll modpow(ll n,ll r){
  ll res = 1;
  while(r){
    if(r & 1)res = res*n%mod;
    n = n*n%mod;
    r >>= 1;
  }
  return res;
}

int main(){
  
  ll n,k;
  cin >> n >> k;
  ll v_sum = 0;
  rep(i,n){
    int v;
    cin >> v;
    v_sum = (v_sum + v)%mod;
  }
  ll res = 0;
  res = (modpow(2,k)-1+mod)%mod;
  res = res*v_sum%mod;
  res = res*modpow(n,k)%mod;
  res = res*modpow(modpow(n,k),mod-2)%mod;
  res = (res+v_sum)%mod;
  cout << res << "\n";


  return 0;
}