View Compilation Error

0_0_37538442_355.cpp: In function 'int C(int, int)':
0_0_37538442_355.cpp:36:14: error: 'fac' was not declared in this scope
     int up = fac[n];
              ^
0_0_37538442_355.cpp:38:38: error: 'binpow' was not declared in this scope
     return (up * binpow(down, mod - 2)) % mod;
                                      ^