func_code_string: #include <bits/stdc++.h>   using namespace std;   const int64_t N = 1e3 + 3;   const int64_t mod = 998244353;   int64_t f[N][2][2][2 * N];   int64_t more(int64_t x, int64_t y, int64_t u, int64_t v) {     if (x == y) {       if (u != x || v != y) return 1;       return 0;     }     if (u != x && v != y) return 2;     return 0;   }   int32_t main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int64_t n, k;     cin >> n >> k;     f[1][0][1][2] = 1;     f[1][0][0][1] = 1;     f[1][1][1][1] = 1;     f[1][1][0][2] = 1;     for (int64_t i = 1; i < n; i++)       for (int64_t x = 0; x < 2; x++)         for (int64_t y = 0; y < 2; y++)           for (int64_t c = 1; c <= 2 * i; c++) {             for (int64_t nx = 0; nx < 2; nx++)               for (int64_t ny = 0; ny < 2; ny++) {                 int64_t _c = c + more(x, y, nx, ny);                 (f[i + 1][nx][ny][_c] += f[i][x][y][c]) %= mod;               }           }     cout << (f[n][0][0][k] + f[n][0][1][k] + f[n][1][0][k] + f[n][1][1][k]) % mod;   }   