View Compilation Error

0_0_17990601_7882.cpp: In function 'long long int C(long long int, long long int)':
0_0_17990601_7882.cpp:26:7: error: 'fac' was not declared in this scope
     m=fac[n];
       ^
0_0_17990601_7882.cpp: In function 'long long int func(long long int, long long int, long long int, long long int)':
0_0_17990601_7882.cpp:51:27: error: too many arguments to function 'long long int Lucas(long long int, long long int)'
     return Lucas(a+b,a,mod);
                           ^
0_0_17990601_7882.cpp:34:4: note: declared here
 LL Lucas(LL n,LL m){
    ^