// ＵＴＦ−８

#include<bits/stdc++.h>
/* #include<atcoder/all> */
/* using namespace atcoder; */

using namespace std;
using ll = long long int;
using lc = complex<ll>;

template<class T>bool chmax(T &a, const T &b) { return (a<b ? (a=b,1) : 0); }
template<class T>bool chmin(T &a, const T &b) { return (a>b ? (a=b,1) : 0); }

int main(void) {
    constexpr ll MOD = 0 ? 1e9+7 : 998244353;
    constexpr double PI = acos(-1);
    constexpr double eps = 1e-10;
    cout << fixed << setprecision(32);
    cin.tie(0); ios::sync_with_stdio(false);

    auto powm = [&](ll x, ll b) {
        ll r = 1;
        while(b) {
            if(b&1) (r *= x) %= MOD;
            (x *= x) %= MOD;
            b >>= 1;
        }
        return r;
    };
    if(1) {
        ll n, k;
        cin >> n >> k;

        vector<ll> a(n);
        for(auto &e: a) cin >> e;
        ll x = accumulate(begin(a), end(a), 0ll, [&](ll a, ll b){return (a+b)%MOD;});
        x %= MOD;

        ll t = 1;
        (t *= x) %= MOD;
        (t *= powm(2, k)) %= MOD;
        cout << (t)%MOD << endl;;
    }

    return 0;
}