View Compilation Error

0_0_37758551_6538.cpp:3:1: error: 'mod' does not name a type
 mod = 998244353;
 ^
0_0_37758551_6538.cpp: In function 'int main()':
0_0_37758551_6538.cpp:33:62: error: 'P' was not declared in this scope
                 dp[i][0] = (1ll * dp[i - 1][0] + dp[i][0]) % P;
                                                              ^
0_0_37758551_6538.cpp:35:62: error: 'P' was not declared in this scope
                 dp[i][0] = (1ll * dp[i - 1][1] + dp[i][0]) % P;
                                                              ^
0_0_37758551_6538.cpp:40:62: error: 'P' was not declared in this scope
                 dp[i][1] = (1ll * dp[i - 1][1] + dp[i][1]) % P;
                                                              ^
0_0_37758551_6538.cpp:42:62: error: 'P' was not declared in this scope
                 dp[i][1] = (1ll * dp[i - 1][0] + dp[i][1]) % P;
                                                              ^
0_0_37758551_6538.cpp:45:55: error: 'P' was not declared in this scope
         cout << (1ll * dp[n * 2][0] + dp[n * 2][1]) % P << endl;
                                                       ^