foo.cc: In function 'int main()':
foo.cc:32:43: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |                         for (int i = 0; i < r.size() - 1; i++)
      |                                         ~~^~~~~~~~~~~~~~
foo.cc:40:39: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   40 |                 for (int i = k + 1; i < q.size(); i++) cout << q[i];
      |                                     ~~^~~~~~~~~~

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