/in/foo.cc: In member function 'Matrix Matrix::operator^(ll)':
/in/foo.cc:43:7: warning: unused variable 'i' [-Wunused-variable]
   int i, j;
       ^
/in/foo.cc:43:10: warning: unused variable 'j' [-Wunused-variable]
   int i, j;
          ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:57:25: warning: format '%d' expects argument of type 'int*', but argument 3 has type 'long long int*' [-Wformat=]
  scanf("%d%I64d", &k, &n);
                         ^