View Compilation Error

0_0_38744488_19426.cpp: In function 'void solve()':
0_0_38744488_19426.cpp:41:9: error: 'num' was not declared in this scope; did you mean 'enum'?
   41 |         num[i] = 0;
      |         ^~~
      |         enum
0_0_38744488_19426.cpp:64:13: error: 'num' was not declared in this scope; did you mean 'enum'?
   64 |             num[j] += (C(i.first, j) % mod * i.second % mod) % mod;
      |             ^~~
      |             enum
0_0_38744488_19426.cpp:64:24: error: 'C' was not declared in this scope
   64 |             num[j] += (C(i.first, j) % mod * i.second % mod) % mod;
      |                        ^
0_0_38744488_19426.cpp:70:16: error: 'num' was not declared in this scope; did you mean 'enum'?
   70 |         ans ^= num[i];
      |                ^~~
      |                enum