View Compilation Error

0_0_23230941_23942.cpp: In function 'll sum(ll)':
0_0_23230941_23942.cpp:32:28: error: 'MOD' was not declared in this scope
     ll t1 = (x * (x + 1) % MOD) * ((2 * x + 1) % MOD);
                            ^
0_0_23230941_23942.cpp:33:65: error: 'qpow' was not declared in this scope
     ll t2 = ((3 * x * x + 3 * x - 1) % MOD) * qpow(30ll, MOD - 2);
                                                                 ^