#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000001
#define Inf64 1000000000000000001
struct combi{
	deque<mint> kaijou;
	deque<mint> kaijou_;
	
	combi(int n){
		kaijou.push_back(1);
		for(int i=1;i<=n;i++){
			kaijou.push_back(kaijou[i-1]*i);
		}
		
		mint b=kaijou[n].inv();
		
		kaijou_.push_front(b);
		for(int i=1;i<=n;i++){
			int k=n+1-i;
			kaijou_.push_front(kaijou_[0]*k);
		}
	}
	
	mint combination(int n,int r){
		if(r>n)return 0;
		mint a = kaijou[n]*kaijou_[r];
		a *= kaijou_[n-r];
		return a;
	}
	
	mint junretsu(int a,int b){
		mint x = kaijou_[a]*kaijou_[b];
		x *= kaijou[a+b];
		return x;
	}
	
	mint catalan(int n){
		return combination(2*n,n)/(n+1);
	}
	
};


combi C(400005);

int main(){
	int N,K;
	cin>>N>>K;
	vector<long long> a(N);
	rep(i,N)cin>>a[i];
	sort(a.begin(),a.end());
	vector<mint> cnt(N+1,0);
	cnt[0] = C.kaijou[N];
	cnt[0] *= N;
	for(int i=1;i<=N;i++){
		if(K*2<=N){
			int rem = N - K*2;
			if(rem >= i){
				mint tt = N - K*2 + 1;
				tt *= C.combination(rem,i);
				cnt[i] += tt;
				
			}
		}
		int l = N - K*2 + 1;
		int r = N - K - 1;
		if(r<0)continue;
		l = max({l,0,i});
		if(l<=r){
			l -= i;
			r -= i;
			mint tt =  C.junretsu(i+1,r);
			if(l!=0)tt -= C.junretsu(i+1,l-1);
			cnt[i] += tt*2;
			if(i==1){
					//cout<<tt.val()<<endl;
				}
		}
	}
	for(int i=1;i<=N;i++){
		cnt[i] += C.combination(N,i);
		cnt[i] *= C.kaijou[i];
		cnt[i] *= C.kaijou[N-i];
	}
	rep(i,N+1){
		mint tt = C.kaijou[N] * N;
		cnt[i] = tt - cnt[i];
	}
	a.insert(a.begin(),0);
	mint ans = 0;
	rep(i,N){
		mint tt = cnt[i+1] - cnt[i];
		tt *= a[i+1];
		ans += tt;
	}
	cout<<ans.val()<<endl;
	
	return 0;
}