#include <cstdio>
#include <algorithm>
#include <cstring>
#include <vector>
#include <queue>
#include <cassert>
#include <cmath>
#include <list> 
typedef long long LL; 
typedef long double LD;
typedef std::pair<int, int> pii;
typedef std::list<int>::iterator IT;
#define MP std::make_pair
#define fi first
#define se second
#define clr(f, n) memset(f, 0, n << 2)
#define cpy(f, g, n) memcpy(f, g, n << 2)
int read()
{
	int s = 0, f = 1;
	char c = getchar();
	while (!(c >= '0' && c <= '9'))
		f ^= c == '-', c = getchar();
	while (c >= '0' && c <= '9')
		s = s * 10 + (c - '0'), c = getchar();
	return f ? s : -s;
}
const int MAXN = 200005, MOD = 998244353, G = 3, invG = (MOD + 1) / G;
auto fplus = [](int x, int y){ return x + y >= MOD ? x + y - MOD : x + y; };
auto fminus = [](int x, int y){ return x >= y ? x - y : x + MOD - y; };
auto Fplus = [](int &x, int y){ return x = fplus(x, y); };
auto Fminus = [](int &x, int y){ return x = fminus(x, y); };
int fpow(int x, int y = MOD - 2)
{
	int res = 1;
	for (; y; y >>= 1, x = (LL)x * x % MOD)
		if (y & 1) res = (LL)res * x % MOD;
	return res;
} 
int n, m, a[MAXN], b[MAXN];
namespace Poly
{
	int tr[MAXN << 2], lst = 0, f[MAXN << 2], g[MAXN << 2];
	void set_tr(int n)
	{
		if (lst == n) return ;
		n = lst;
		for (int i = 1; i < n; i++)
			tr[i] = (tr[i >> 1] << 1) | ((i & 1) ? (n >> 1) : 0);
	}
	void fmult(int a[], int b[], int n)
	{
		for (int i = 0; i < n; i++)
			a[i] = (LL)a[i] * b[i] % MOD;
	}
	void NTT(int g[], int n, bool flg)
	{
		static int f[MAXN << 2], pw[MAXN << 2];
		set_tr(n), pw[0] = 1;
		for (int i = 0; i < n; i++) g[i] = f[tr[i]];
		for (int l = 1; l < n; l <<= 1)
		{
			int tG = fpow(flg ? invG : G, (MOD - 1) / (l + l));
			for (int i = 0; i < l; i++) pw[i] = (LL)tG * pw[i - 1] % MOD;
			for (int s = 0; s < n; s += l + l)
				for (int p = 0; p < l; p++)
				{
					int x = f[s | p], y = (LL)pw[p] * f[s | p | l] % MOD;
					f[s | p] = fplus(x, y), f[s | p | l] = fminus(x, y);
				}
		}
		if (flg)
		{
			int invn = fpow(n);
			for (int i = 0; i < n; i++)
				g[i] = (LL)f[i] * invn % MOD;
		}
		else cpy(g, f, n);
	}
	void times(int a[], int n, int b[], int m, int lim)
	{
		int len;
		for (len = 1; len <= n + m; len <<= 1) ;
		clr(f, len), clr(g, len);
		cpy(f, a, n + 1), cpy(g, b, m + 1);
		NTT(f, len, 0), NTT(g, len, 0);
		fmult(f, g, len), NTT(f, len, 1);
		cpy(a, f, len), clr(a + lim, len - lim);
	}
}
std::vector<int> f[MAXN << 2];
int len[MAXN << 2], fac[MAXN], ifac[MAXN], inv[MAXN];
#define ls (x << 1)
#define rs (x << 1 | 1)
void maintain(int x)
{
	len[x] = len[ls] + len[rs];
}
void build(int x, int l, int r)
{
	if (l == r)
	{
		f[x].resize((len[x] = b[l] - 1) + 1);		
		for (int i = 0; i < b[l]; i++)
			f[x][i] = (LL)ifac[i] * ifac[b[l] - i] % MOD;
		return ;
	}
	int mid = (l + r) >> 1;
	build(ls, l, mid), build(rs, mid + 1, r);
	maintain(x);
}
int main()
{
	n = read(), m = read();
	for (int i = 1; i <= n; i++) a[i] = read();
	for (int i = 1; i <= n; i++) b[i] = read();
	inv[1] = 1;
	for (int i = 2; i <= m; i++)
		inv[i] = MOD - (LL)MOD / i * inv[MOD % i] % MOD;
	fac[0] = ifac[0] = 1;
	for (int i = 1; i <= m; i++)
	{
		fac[i] = (LL)fac[i - 1] * i % MOD;
		ifac[i] = (LL)ifac[i - 1] * inv[i] % MOD;
	}
	build(1, 1, n);
	return 0;
}