For problem statement at 1000-1999/1600-1699/1610-1619/1613/problemF.txt this is a correct solution, but verifier at 1000-1999/1600-1699/1610-1619/1613/verifierF.go ends with All tests passed can you fix the verifier? ```go
package main

import (
	"fmt"
	"io"
	"os"
)

const MOD = 998244353
const G = 3

func power(base, exp int) int {
	res := 1
	base %= MOD
	for exp > 0 {
		if exp%2 == 1 {
			res = res * base % MOD
		}
		base = base * base % MOD
		exp /= 2
	}
	return res
}

var rt, irt [][]int

func initNTT(maxLen int) {
	k := 0
	for (1 << k) <= maxLen {
		k++
	}
	rt = make([][]int, k)
	irt = make([][]int, k)
	for i := 1; i < k; i++ {
		l := 1 << i
		wlen := power(G, (MOD-1)/l)
		iwlen := power(wlen, MOD-2)
		rt[i] = make([]int, l/2)
		irt[i] = make([]int, l/2)
		w := 1
		iw := 1
		for j := 0; j < l/2; j++ {
			rt[i][j] = w
			irt[i][j] = iw
			w = w * wlen % MOD
			iw = iw * iwlen % MOD
		}
	}
}

func ntt(a []int, invert bool) {
	n := len(a)
	for i, j := 1, 0; i < n; i++ {
		bit := n >> 1
		for j&bit != 0 {
			j ^= bit
			bit >>= 1
		}
		j ^= bit
		if i < j {
			a[i], a[j] = a[j], a[i]
		}
	}
	k := 1
	for l := 2; l <= n; l <<= 1 {
		var w []int
		if invert {
			w = irt[k]
		} else {
			w = rt[k]
		}
		half := l / 2
		for i := 0; i < n; i += l {
			for j := 0; j < half; j++ {
				u := a[i+j]
				v := a[i+j+half] * w[j] % MOD
				a[i+j] = u + v
				if a[i+j] >= MOD {
					a[i+j] -= MOD
				}
				a[i+j+half] = u - v + MOD
				if a[i+j+half] >= MOD {
					a[i+j+half] -= MOD
				}
			}
		}
		k++
	}
	if invert {
		invN := power(n, MOD-2)
		for i := 0; i < n; i++ {
			a[i] = a[i] * invN % MOD
		}
	}
}

func multiply(a, b []int) []int {
	if len(a) == 0 || len(b) == 0 {
		return []int{}
	}
	if len(a)*len(b) <= 256 {
		res := make([]int, len(a)+len(b)-1)
		for i, va := range a {
			if va == 0 {
				continue
			}
			for j, vb := range b {
				res[i+j] = (res[i+j] + va*vb) % MOD
			}
		}
		return res
	}
	n := 1
	for n < len(a)+len(b)-1 {
		n <<= 1
	}
	fa := make([]int, n)
	fb := make([]int, n)
	copy(fa, a)
	copy(fb, b)
	ntt(fa, false)
	ntt(fb, false)
	for i := 0; i < n; i++ {
		fa[i] = fa[i] * fb[i] % MOD
	}
	ntt(fa, true)
	return fa[:len(a)+len(b)-1]
}

func main() {
	bBytes, err := io.ReadAll(os.Stdin)
	if err != nil {
		return
	}
	ptr := 0
	readInt := func() int {
		for ptr < len(bBytes) && (bBytes[ptr] < '0' || bBytes[ptr] > '9') {
			ptr++
		}
		if ptr >= len(bBytes) {
			return 0
		}
		res := 0
		for ptr < len(bBytes) && bBytes[ptr] >= '0' && bBytes[ptr] <= '9' {
			res = res*10 + int(bBytes[ptr]-'0')
			ptr++
		}
		return res
	}

	n := readInt()
	if n == 0 {
		return
	}

	adj := make([][]int, n+1)
	for i := 0; i < n-1; i++ {
		u := readInt()
		v := readInt()
		adj[u] = append(adj[u], v)
		adj[v] = append(adj[v], u)
	}

	q := make([]int, 0, n)
	q = append(q, 1)
	visited := make([]bool, n+1)
	visited[1] = true
	d := make([]int, n+1)

	for i := 0; i < len(q); i++ {
		u := q[i]
		for _, v := range adj[u] {
			if !visited[v] {
				visited[v] = true
				d[u]++
				q = append(q, v)
			}
		}
	}

	freq := make(map[int]int)
	for i := 1; i <= n; i++ {
		if d[i] > 0 {
			freq[d[i]]++
		}
	}

	fact := make([]int, n+1)
	invFact := make([]int, n+1)
	fact[0] = 1
	invFact[0] = 1
	for i := 1; i <= n; i++ {
		fact[i] = fact[i-1] * i % MOD
	}
	invFact[n] = power(fact[n], MOD-2)
	for i := n - 1; i >= 1; i-- {
		invFact[i] = invFact[i+1] * (i + 1) % MOD
	}

	getPoly := func(D, C int) []int {
		poly := make([]int, C+1)
		poly[0] = 1
		D_pow := 1
		for j := 1; j <= C; j++ {
			D_pow = D_pow * D % MOD
			comb := fact[C] * invFact[j] % MOD * invFact[C-j] % MOD
			poly[j] = comb * D_pow % MOD
		}
		return poly
	}

	var polys [][]int
	for D, C := range freq {
		polys = append(polys, getPoly(D, C))
	}
	if len(polys) == 0 {
		polys = append(polys, []int{1})
	}

	initNTT(1 << 20)

	for len(polys) > 1 {
		min1, min2 := -1, -1
		for i := 0; i < len(polys); i++ {
			if min1 == -1 || len(polys[i]) < len(polys[min1]) {
				min2 = min1
				min1 = i
			} else if min2 == -1 || len(polys[i]) < len(polys[min2]) {
				min2 = i
			}
		}
		a := polys[min1]
		b := polys[min2]
		nextPolys := make([][]int, 0, len(polys)-1)
		for i := 0; i < len(polys); i++ {
			if i != min1 && i != min2 {
				nextPolys = append(nextPolys, polys[i])
			}
		}
		nextPolys = append(nextPolys, multiply(a, b))
		polys = nextPolys
	}

	finalPoly := polys[0]
	ans := 0
	for k := 0; k < len(finalPoly); k++ {
		if n-k < 0 {
			break
		}
		term := finalPoly[k] * fact[n-k] % MOD
		if k%2 == 1 {
			ans = (ans - term + MOD) % MOD
		} else {
			ans = (ans + term) % MOD
		}
	}

	fmt.Println(ans)
}
```