#include <iostream>
using namespace std;

#include <iostream>
#include <cassert>

template<long long mod>
class modint{
private:
  using T = long long;
  T a;
public:
  constexpr modint(const long long x = 0) noexcept : a((x%mod+mod)%mod) {}
  constexpr T& value() noexcept { return a; }
  constexpr const T& value() const noexcept { return a; }
  constexpr modint operator-() const noexcept {
    return modint(0) -= *this;
  }
  constexpr modint operator+(const modint& rhs) const noexcept {
    return modint(*this) += rhs;
  }
  constexpr modint operator-(const modint& rhs) const noexcept {
    return modint(*this) -= rhs;
  }
  constexpr modint operator*(const modint& rhs) const noexcept {
    return modint(*this) *= rhs;
  }
  constexpr modint operator/(const modint& rhs) const noexcept {
    return modint(*this) /= rhs;
  }
  constexpr modint& operator+=(const modint& rhs) noexcept {
    a += rhs.a;
    if(a >= mod) a -= mod;
    return *this;
  }
  constexpr modint& operator-=(const modint& rhs) noexcept {
    if(a < rhs.a) a += mod;
    a -= rhs.a;
    return *this;
  }
  constexpr modint& operator*=(const modint& rhs) noexcept {
    a = a*rhs.a%mod;
    return *this;
  }
  constexpr modint& operator/=(const modint& rhs) noexcept {
    return *this *= rhs.inv();
  }
  constexpr bool operator==(const modint& rhs) const noexcept {
    return a == rhs.a;
  }
  constexpr bool operator!=(const modint& rhs) const noexcept {
    return not (*this == rhs);
  }
  constexpr modint pow(long long k) const noexcept {
    modint ret(1);
    modint x = k > 0 ? *this : this->inv();
    k = abs(k);
    while(k > 0){
      if(k&1) ret *= x;
      x *= x;
      k >>= 1;
    }
    return ret;
  }
  constexpr modint inv() const noexcept {
    return pow(mod-2);
  }
  friend std::ostream& operator<<(std::ostream &os, const modint &X) noexcept {
    return os << X.a;
  }
  friend std::istream& operator>>(std::istream &is, modint &X) noexcept {
    is >> X.a;
    X.a %= mod;
    if(X.a < 0) X.a += mod;
    return is;
  }
};

#include <vector>
#include <cassert>

template<typename T>
struct Combination {
private:
  int sz;
  vector<T> F, F_;
public:
  Combination(int sz) : sz(sz), F(sz+1), F_(sz+1) {
    F[0] = 1;
    for(int i = 0; i < sz; ++i) F[i+1] = F[i]*(i+1);
    F_.back() = (T)1/F.back();
    for(int i = sz-1; i >= 0; --i) F_[i] = F_[i+1]*(i+1);
  }
  T C(int n, int k){
    assert(n <= sz);
    if(n < 0 or k > n) return (T)0;
    return F[n]*F_[k]*F_[n-k];
  }
  T P(int n, int k){
    assert(n <= sz);
    if(n < 0 or k > n) return (T)0;
    return F[n]*F_[n-k];
  }
};

int main(){
  using mint = modint<998244353>;
  int n, k;
  cin >> n >> k;
  if(n == 1){
    int ans[] = {1,1,3,3,3,1,1};
    cout << ans[k] << '\n';
    return 0;
  }
  Combination<mint> comb(n*2+4);
  mint ans = comb.C(n*2+4,k);
  if(k%2 == 0){
    ans += comb.C(n+2,k/2)*3;
  }else if(n%2){
    ans += comb.C(n+1,k/2)*2;
  }
  cerr << ans << '\n';
  cout << ans/4 << '\n';
}