#line 1 "Main.cpp"

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <set>
#include <atcoder/modint>
#line 2 "nachia-library\\math\\combination.hpp"

#line 4 "nachia-library\\math\\combination.hpp"


namespace nachia{

template<class Modint>
class Comb{
private:
    ::std::vector<Modint> F;
    ::std::vector<Modint> iF;
public:
    Comb(int n){
        F.assign(n+1, Modint(1));
        for(int i=1; i<=n; i++) F[i] = F[i-1] * Modint(i);
        iF.assign(n+1, Modint(1));
        iF[n] = F[n].inv();
        for(int i=n; i>=1; i--) iF[i-1] = iF[i] * Modint(i);
    }
    Modint factorial(int n) const { return F[n]; }
    Modint inv_factorial(int n) const { return iF[n]; }
    Modint inv_of(int n) const { return iF[n] * F[n-1]; }
    Modint comb(int n, int r) const {
        if(n < 0 || n < r || r < 0) return Modint(0);
        return F[n] * iF[r] * iF[n-r];
    }
    Modint inv_comb(int n, int r) const {
        if(n < 0 || n < r || r < 0) return Modint(0);
        return iF[n] * F[r] * F[n-r];
    }
    Modint perm(int n, int r) const {
        if(n < 0 || n < r || r < 0) return Modint(0);
        return F[n] * iF[n-r];
    }
    Modint inv_perm(int n, int r) const {
        if(n < 0 || n < r || r < 0) return Modint(0);
        return iF[n] * F[n-r];
    }
    Modint operator()(int n, int r) const { return comb(n,r); }
};

} // namespace nachia
#line 9 "Main.cpp"

using namespace std;
using i32 = int32_t;
using u32 = uint32_t;
using i64 = int64_t;
using u64 = uint64_t;
#define rep(i,n) for(int i=0; i<(int)(n); i++)


const i64 INF = 1001001001001001001;
using modint = atcoder::static_modint<998244353>;



int main(){
    int A, B; cin >> A >> B;
    nachia::Comb<modint> comb(200100);
    auto ans = comb(A+B-2,A-1);
    cout << ans.val() << '\n';
    return 0;
}


struct ios_do_not_sync{
    ios_do_not_sync(){
        std::ios::sync_with_stdio(false);
        std::cin.tie(nullptr);
    }
} ios_do_not_sync_instance;