answer.code: In function ‘long long int play_game(long long int, int, long long int, std::vector<long long int>, std::vector<long long int>)’:
answer.code:16:27: error: ‘l’ was not declared in this scope
   16 |                         a[l[i]]++;
      |                           ^
answer.code:17:27: error: ‘r’ was not declared in this scope
   17 |                         a[r[i + 1]]--;
      |                           ^
answer.code:28:32: error: ‘r’ was not declared in this scope
   28 |                         res += r[i] - l[i] + 1;
      |                                ^
answer.code:28:39: error: ‘l’ was not declared in this scope
   28 |                         res += r[i] - l[i] + 1;
      |                                       ^
answer.code:33:1: warning: control reaches end of non-void function [-Wreturn-type]
   33 | }
      | ^