View Compilation Error

0_0_21596757_25761.cpp:8:1: error: expected ',' or ';' before 'const'
 const int MOD = 998244353;
 ^
0_0_21596757_25761.cpp: In member function 'void Trie::solve()':
0_0_21596757_25761.cpp:69:57: error: 'MOD' was not declared in this scope
               dp[i+1][nxt[j][a]][s|ed[0][nxt[j][a]]] %= MOD;
                                                         ^
0_0_21596757_25761.cpp:80:34: error: 'MOD' was not declared in this scope
      ans = (ans + dp[m][i][j]) % MOD;
                                  ^