#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
#define MOD 998244353
#define MAX 303030
ll mpow(ll x, ll y = MOD - 2) {
	ll mul = x;
	ll ans = 1;
	while (y) {
		if (y & 1) ans = (ans * mul) % MOD;
		y >>= 1;
		mul = (mul * mul) % MOD;
	}
	return ans;
}
ll ifact[MAX];
ll fact[MAX];
inline ll C(int N, int R) {
	ll res = fact[N] * ifact[R];
	res %= MOD;
	res = res * ifact[N - R];
	res %= MOD;
	return res;
}
inline ll P(int N, int R) {
	ll res = fact[N] * ifact[N - R];
	res %= MOD;
	return res;
}
signed main() {
	ios::sync_with_stdio(false), cin.tie(0);
	int i;
	fact[0] = 1;
	const int X = 300'010;
	for (i = 1; i <= X; i++) fact[i] = (fact[i - 1] * i) % MOD;
	ifact[X] = mpow(fact[X]);
	for (i = X; i >= 1; i--) ifact[i - 1] = (ifact[i] * i) % MOD;

	int e, p, w, t;
	cin >> e >> p >> w >> t;
	int N = e + p + w;
	ll sum = 0;
	for (i = 1; i <= N - e + 1; i++) {
		ll mul = C(N - i, e - 1);
		if (p + t <= i) mul *= mpow(N - i - e + 1 + t, p), mul %= MOD;
		else if (t < i) {
			mul *= mpow(N - i - e + 1 + t, i - t);
			mul %= MOD;
			mul *= P(N - e - i + t, p - i + t);
			mul %= MOD;
		}
		else {
			mul *= C(N - e, w);
			mul %= MOD;
			mul *= fact[p];
			mul %= MOD;
		}
		sum = (sum + mul) % MOD;
	}
	ll div = C(N, w);
	div %= MOD;
	div *= C(N - w, e);
	div %= MOD;
	div *= fact[p];
	div %= MOD;
	sum *= mpow(div);
	sum %= MOD;
	cout << sum;
}