/in/foo.cc: In function 'int main()':
/in/foo.cc:56:20: warning: format '%lld' expects argument of type 'long long int*', but argument 2 has type 'long long int' [-Wformat=]
    scanf("%lld",res);
                    ^
/in/foo.cc:55:7: warning: 'res' may be used uninitialized in this function [-Wmaybe-uninitialized]
    ll res;
       ^~~