foo.cc: In function 'int main()':
foo.cc:45:26: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   45 |     while (answer.size() < n) {
      |            ~~~~~~~~~~~~~~^~~
foo.cc:52:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |     for (int i = 0; i < answer.size(); i++) {
      |                     ~~^~~~~~~~~~~~~~~

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