#include<iostream>
#include<algorithm>
#include<numeric>//accumulate(be,en,0)
#include<cstring>//rfind("string"),s.find(string,begin)!=s.npos,find_first _of(),find_last_of()
#include<string>//to_string(value),s.substr(int begin, int length);
#include<cstdio>
#include<cmath>
#include<vector>//res.erase(unique(res.begin(), res.end()), res.end()),reverse(q.begin(),q.end()),vector<int>().swap(at[mx])
#include<queue>//priority_queue(big) /priority_queue<int, vector<int>, greater<int>> q(small)
#include<stack>
//#include<map>//unordered_map
#include<set>//iterator,insert(),erase(),lower(>=)/upper_bound(>)(value)/find()return end()
#include<unordered_map>
#include<unordered_set>
#include<bitset>//size,count(size of 1),reset(to 0),any(have 1?)
//#include<ext/pb_ds/assoc_container.hpp>//gp_hash_table
//#include<ext/pb_ds/hash_policy.hpp>
//using namespace __gnu_pbds;
#define int long long//__int128 2^127-1(GCC)
#define PII pair<int,int>
#define f first
#define s second
using namespace std;
const int inf = 0x3f3f3f3f3f3f3f3f, N = 2e5 + 5, mod = 998244353;
int fpow(int x, int r)
{
int result = 1;
while (r)
{
if (r & 1)result = result * x % mod;
r >>= 1;
x = x * x % mod;
}
return result;
}
namespace binom {
int fac[N], ifac[N];
int __ = []
{
fac[0] = 1;
for (int i = 1; i <= N - 5; i++)
fac[i] = fac[i - 1] * i % mod;
ifac[N - 5] = fpow(fac[N - 5], mod - 2);
for (int i = N - 5; i; i--)
ifac[i - 1] = ifac[i] * i % mod;
return 0;
}();
inline int C(int n, int m)
{
if (n < m || m < 0)return 0;
return fac[n] * ifac[m] % mod * ifac[n - m] % mod;
}
inline int A(int n, int m)
{
if (n < m || m < 0)return 0;
return fac[n] * ifac[n - m] % mod;
}
}
using namespace binom;
signed main()
{
ios_base::sync_with_stdio(0); cin.tie(0), cout.tie(0);
int n, m;
cin >> n >> m;
int res = 0;
for (int i = 1; i <= n; i++)
{
int l = i - 1;
int r = n - i;
res = (res + C(m - 1, l) * C(m-1-l, r) % mod) % mod;
}
cout << res << '\n';
}