/in/foo.cc: In function 'int main()':
/in/foo.cc:4:13: error: expected primary-expression before 'long'
    4 | #define int long long
      |             ^~~~
/in/foo.cc:13:30: note: in expansion of macro 'int'
   13 |                 s+=to_string(int(i));
      |                              ^~~