#include <iostream>
#include <cmath>
#include <algorithm>
#include <set>
#include <map>
#include <vector>
#include <string>
#include <queue>

using namespace std;
const int N = 1000 + 12;
const int mod = 998244353;

int d[N][2 * N][5];
int n, k;

inline void read() {
    cin >> n >> k;
}

int getCnt(int mask, int nmask) {
    if (nmask == mask) {
        return 0;
    }
    if (mask == 0 && nmask == 1) {
        return 0;
    } else if (mask == 1 && nmask == 0) {
        return 1;
    } else if (mask == 0 && nmask == 2) {
        return 0;
    } else if (mask == 2 && nmask == 0) {
        return 1;
    } else if (mask == 0 && nmask == 3) {
        return 1;
    } else if (mask == 3 && nmask == 0) {
        return 1;
    } else if (mask == 1 && nmask == 2) {
        return 2;
    } else if (mask == 2 && nmask == 1) {
        return 2;
    } else if (mask == 1 && nmask == 3) {
        return 1;
    } else if (mask == 3 && nmask == 1) {
        return 0;
    } else if (mask == 2 && nmask == 3) {
        return 1;
    } else if (mask == 3 && nmask == 2) {
        return 0;
    }
}

inline void solve() {
    d[0][0][0] = 1;
    d[0][0][1] = 1;
    d[0][0][2] = 1;
    d[0][0][3] = 1;

    for (int i = 0; i < n; i++) {
        for (int j = 0; j <= 2 * i; j++) {
            for (int mask = 0; mask < 4; mask++) {
                for (int nmask = 0; nmask < 4; nmask++) {
                    d[i + 1][j + getCnt(mask, nmask)][nmask] += d[i][j][mask];
                    d[i + 1][j + getCnt(mask, nmask)][nmask] %= mod;
                }
            }
        }
    }

    int ans = 0;
    for (int mask = 0; mask < 4; mask++) {
        if (mask == 0 || mask == 3) {
            ans += d[n][k - 1][mask];
        } else if (k > 1) {
            ans += d[n][k - 2][mask];
        }
    }

    ans %= mod;
    cout << ans << endl;
}

int main() {
    read();
    solve();
    return 0;
}