#include <bits/stdc++.h>
using namespace std;

#define double long double

using ll = long long;
using VB = vector<bool>;
using VVB = vector<VB>;
using VVVB = vector<VVB>;
using VC = vector<char>;
using VI = vector<int>;
using VVI = vector<VI>;
using VVVI = vector<VVI>;
using VL = vector<ll>;
using VVL = vector<VL>;
using VVVL = vector<VVL>;
using VVVVL = vector<VVVL>;
using VD = vector<double>;
using VVD = vector<VD>;
using VVVD = vector<VVD>;
//using P = pair<int, int>;

#define REP(i, n) for (int i = 0; i < (int)(n); i++)
#define FOR(i, a, b) for (ll i = a; i < (ll)(b); i++)
#define ALL(a) (a).begin(),(a).end()

constexpr int INF = 1001001001;
constexpr ll LINF = 1001001001001001001ll;
constexpr int DX[] = {1, 1, 0, -1, -1, -1, 0, 1};
constexpr int DY[] = {0, 1, 1, 1, 0, -1, -1, -1};

template< typename T1, typename T2>
inline bool chmax(T1 &a, T2 b) {return a < b && (a = b, true); }
template< typename T1, typename T2>
inline bool chmin(T1 &a, T2 b) {return a > b && (a = b, true); }

const ll MOD = 998244353;

const int MAX_N = 200010;
int par[MAX_N];
int rnk[MAX_N];
int siz[MAX_N];

void init(int n) {
    REP(i,n) {
        par[i] = i;
        rnk[i] = 0;
        siz[i] = 1;
    }
}

int find(int x) {
    if (par[x] == x) {
        return x;
    } else {
        return par[x] = find(par[x]);
    }
}

void unite(int x, int y) {
    x = find(x);
    y = find(y);
    if (x == y) return;
    int s = siz[x] + siz[y];
    if (rnk[x] < rnk[y]) {
        par[x] = y;
    } else {
        par[y] = x;
        if (rnk[x] == rnk[y]) rnk[x]++;
    }
    siz[find(x)] = s;
}

bool same(int x, int y) {
    return find(x) == find(y);
}

int size(int x) {
    return siz[find(x)];
}

ll mod_pow(ll x, ll n, ll mod) {
    ll res = 1;
    while (n > 0) {
        if (n & 1) res = res * x % mod;
        x = x * x % mod;
        n >>= 1;
    }
    return res;
}

ll gcd(ll x, ll y) {
    if (y == 0) return x;
    return gcd(y, x % y);
}

const int MAX_E = 5000, MAX_V = 2500;

struct edge { ll from, to, cost; };

edge es[MAX_E];

ll d[MAX_V];
int V, E;

void shortest_path(int s) {
    for (int i = 0; i < V; i++) d[i] = LINF;
    d[s] = 0;
    REP(j, V) {
        bool update = false;
        for (int i = 0; i < E; i++) {
            edge e = es[i];
            if (d[e.from] != LINF && d[e.to] > d[e.from] + e.cost) {
                d[e.to] = d[e.from] + e.cost;
                update = true;
            }
        }
        if (!update) break;
    }
}

bool find_negative_loop() {
    memset(d, 0, sizeof(d));
    for (int i = 0; i < V; i++) {
        for (int j = 0; j < E; j++) {
            edge e = es[j];
            if (d[e.to] > d[e.from] + e.cost) {
                d[e.to] = d[e.from] + e.cost;
                if (e.to == V - 1 && i == V - 1) return true;
            }
        }
    }
    return false;
}

map<ll, ll> mp;

ll f(ll X) {
    if (mp.find(X) != mp.end()) return mp[X];
    if (X < 5) {
        mp[X] = X;
        return X;
    }
    ll Y = X / 2, Z = X - Y;
    mp[X] = f(Y) * f(Z) % MOD;
    return mp[X];
}

int main() {
    ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    ll a, b, ans = 1;
    cin >> a >> b;
    REP(i, a - 1) ans = ans * (a + b - 2 - i) % MOD;
    REP(i, a - 1) ans = ans * mod_pow(i + 1, MOD - 2, MOD) % MOD;
    cout << ans << endl;
}