0_0_38847947_1537.cpp:2:12: error: expected ',' or ';' before 'long'
2 | #define ll long long
| ^~~~
0_0_38847947_1537.cpp:5:1: note: in expansion of macro 'll'
5 | ll ksm(ll a,ll b)
| ^~
0_0_38847947_1537.cpp: In function 'int main()':
0_0_38847947_1537.cpp:24:20: error: 'ksm' was not declared in this scope
24 | else cout<<(2*n-1)*ksm(3,mod-2)%mod<<'\n';
| ^~~
|