#include using namespace std; #define rep(i,j,n) for(int i=j;i pi; template using vt = vector; template using vvt = vector>; i64 gcd(i64 n, i64 m) {return (m == 0? n : gcd(m, n % m));} i64 lcd(i64 n, i64 m) {return (n / gcd(n, m) * m);} int dx[] = {1, 0, -1, 0}; int dy[] = {0, 1, 0, -1}; const int sz = 510000; i64 fac[sz], finv[sz], inv[sz]; void init() { fac[0] = fac[1] = 1; finv[0] = finv[1] = 1; inv[1] = 1; for(i64 i = 2; i < sz; ++i) { fac[i] = fac[i - 1] * i % mod; inv[i] = mod - inv[mod % i] * (mod / i) % mod; finv[i] = finv[i - 1] * inv[i] % mod; } } i64 get(int n, int k) { return fac[n] * (finv[k] * finv[n - k] % mod) % mod; } int main() { cin.tie(0); ios::sync_with_stdio(false); int n; cin >> n; vt a(n); rep(i, 0, n) cin >> a[i]; init(); i64 ans = 0; rep(i, 0, n) { ans += a[i] * get(n - 1, i); ans %= mod; } cout << ans << endl; }