foo.cc: In function 'int main()':
foo.cc:12:21: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   12 |  while (numb.size() < k) {
      |         ~~~~~~~~~~~~^~~
foo.cc:21:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |  for (int i = 0; i < numb.size(); i++) {
      |                  ~~^~~~~~~~~~~~~

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