#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll MOD = 998244353;
// a^n mod MOD を計算
ll modpow(ll aa, ll n) {
ll res = 1;
while (n > 0) {
if (n % 2 == 1) {
res = res * aa % MOD;
}
aa = aa * aa % MOD;
n /= 2;
}
return res;
}
vector<long long> W;
long long N,M;
int searchc(int mods,long long c,int d){
//cは最初に1を入れる、dは0
for(int i=d;i<N-M+1;i++){
c=c*W[i]; c=c%mods;
searchc(mods,c,i+1);
}
return c;
}
int searchf(int b,int mods,long long f,int d){
//fは最初に1を入れる、dは0
for(int i=d;i<N-M+1;i++){
f=f*b; f=f%mods;
searchf(b,mods,f,i+1);
}
return f;
}
int main() {
long long K,a=0,e;
int mod=998244353;
cin>>N>>M>>K;
for(int i=0;i<N;i++){
cin>>e;
W.push_back(e);
a+=W[i];
}
int C=searchc(mod,1,0);
int F=searchf(a,mod,1,0);
// xの逆元を求める
ll inv = modpow(F, MOD - 2);
// y / x に相当する値
ll z = C * inv % MOD;
cout << z << endl;
}
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