View Compilation Error

0_0_30997558_22708.cpp: In function 'void init(ll, ll, ll)':
0_0_30997558_22708.cpp:47:2: error: 'fac' was not declared in this scope
  fac[0] = fac[1] = 1;
  ^
0_0_30997558_22708.cpp:50:2: error: 'inv' was not declared in this scope
  inv[n-m] = q_pow(fac[n-m],mod-2,mod)%mod;
  ^