#include #include const int Mod = 998244353; int bit[21], bit_inv[21]; long long root[21], root_inv[21]; long long div_mod(long long x, long long y, long long z) { if (x % y == 0) return x / y; else return (div_mod((1 + x / y) * y - x, (z % y), y) * z + x) / y; } long long pow_mod(long long n, int k) { long long N, ans = 1; for (N = n; k > 0; k >>= 1, N = N * N % Mod) if (k & 1) ans = ans * N % Mod; return ans; } void NTT(int k, long long a[], long long z[]) { if (k == 0) { z[0] = a[0]; return; } int i, d = bit[k-1]; long long tmp, *b = (long long*)malloc(sizeof(long long) * d), *c = (long long*)malloc(sizeof(long long) * d), *x = (long long*)malloc(sizeof(long long) * d), *y = (long long*)malloc(sizeof(long long) * d); for (i = 0; i < d; i++) { b[i] = a[i*2]; c[i] = a[i*2+1]; } NTT(k - 1, b, x); NTT(k - 1, c, y); for (i = 0, tmp = 1; i < d; i++, tmp = tmp * root[k] % Mod) { z[i] = (x[i] + y[i] * tmp) % Mod; z[i+d] = (x[i] - y[i] * tmp % Mod + Mod) % Mod; } free(b); free(c); free(x); free(y); } void NTT_reverse(int k, long long z[], long long a[]) { if (k == 0) { a[0] = z[0]; return; } int i, d = bit[k-1]; long long tmp, *b = (long long*)malloc(sizeof(long long) * d), *c = (long long*)malloc(sizeof(long long) * d), *x = (long long*)malloc(sizeof(long long) * d), *y = (long long*)malloc(sizeof(long long) * d); for (i = 0; i < d; i++) { x[i] = z[i*2]; y[i] = z[i*2+1]; } NTT_reverse(k - 1, x, b); NTT_reverse(k - 1, y, c); for (i = 0, tmp = 1; i < d; i++, tmp = tmp * root_inv[k] % Mod) { a[i] = (b[i] + c[i] * tmp) % Mod; a[i+d] = (b[i] - c[i] * tmp % Mod + Mod) % Mod; } free(b); free(c); free(x); free(y); } void prod_poly_NTT(int da, int db, long long a[], long long b[], long long c[]) { int i, k; for (k = 0, bit[0] = 1; bit[k] < da + db; k++) bit[k+1] = bit[k] * 2; for (i = k - 1, bit_inv[k] = div_mod(1, bit[k], Mod); i >= 0; i--) bit_inv[i] = bit_inv[i+1] * 2 % Mod; for (i = k - 1, root[k] = pow_mod(3, (Mod - 1) / bit[k]), root_inv[k] = pow_mod(3, Mod - 1 - (Mod - 1) / bit[k]); i >= 0; i--) { root[i] = root[i+1] * root[i+1] % Mod; root_inv[i] = root_inv[i+1] * root_inv[i+1] % Mod; } for (i = da; i < bit[k]; i++) a[i] = 0; for (i = db; i < bit[k]; i++) b[i] = 0; long long *x = (long long*)malloc(sizeof(long long) * bit[k]), *y = (long long*)malloc(sizeof(long long) * bit[k]), *z = (long long*)malloc(sizeof(long long) * bit[k]); NTT(k, a, x); NTT(k, b, y); for (i = 0; i < bit[k]; i++) z[i] = x[i] * y[i] % Mod; NTT_reverse(k, z, c); for (i = 0; i < da + db; i++) c[i] = c[i] * bit_inv[k] % Mod; free(x); free(y); free(z); } int main() { int N; scanf("%d", &N); int i, j, k; long long a[262145], b[262145], c[262145], ans[100001], fact[100001], fact_inv[100001]; for (i = 1, fact[0] = 1; i <= N; i++) fact[i] = fact[i-1] * i % Mod; for (i = N - 1, fact_inv[N] = div_mod(1, fact[N], Mod); i >= 0; i--) fact_inv[i] = fact_inv[i+1] * (i + 1) % Mod; for (i = 0; i < N - 1; i++) a[i] = fact_inv[i] * (i + 1) % Mod; for (k = N, ans[0] = fact[N-2]; k > 0; k >>= 1) { if ((k & 1) == 1) { for (i = 0; i < N - 1; i++) b[i] = ans[i]; prod_poly_NTT(N - 1, N - 1, a, b, c); for (i = 0; i < N - 1; i++) ans[i] = c[i]; } prod_poly_NTT(N - 1, N - 1, a, a, b); for (i = 0; i < N - 1; i++) a[i] = b[i]; } printf("%lld\n", div_mod(ans[N-2], pow_mod(N, N - 2), Mod)); fflush(stdout); return 0; }