func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 50010;   const int mod = 998244353;   int n;   const int a[16] = {0,   4,  8,   -1, 16,  -10, 4,  -12,                      -48, 26, -44, 15, -16, -4,  -4, -1};   int f[N] = {0,    0,    0,     24,    4,      240,    204,     1316,               2988, 6720, 26200, 50248, 174280, 436904, 1140888, 3436404};   int main() {     for (int i = 16; i <= 50000; i++)       for (int j = 0; j <= 15; j++)         f[i] = ((f[i] + 1ll * a[j] * f[i - j - 1]) % mod + mod) % mod;     scanf( %d , &n);     printf( %d n , f[n]);     return 0;   }   