#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
#include <iostream>
typedef long long ll;
using namespace std;

int N, A[100000];
ll res;

int main() {
	scanf("%d", &N);
	for (int i = 0; i < N; i++) {
		scanf("%d", &A[i]);
		if (A[i] >= 998244353)A[i] -= 998244353;
	}
	for (int i = 0; i < N; i++){
	    res += (ll)A[i] * (N - 1);
	}
	for (int i = 0; i < N; i++) {
		for (int j = i + 1; j < N; j++) {
			if (A[i] + A[j] >= 998244353)res -= 998244353ll;
		}
	}
	printf("%lld\n", res);
}