#include #include using namespace std; using ll = long long; int main() { int N; cin >> N; vector c(N); for (ll i = 0; i < N; i++) { cin >> c[i]; } ll ans = 1; for (int i = 0; i < N - 1; i++) { ans = (ans * 2LL) % 998244353; } cout << ans << endl; }