foo.cc: In function 'int main()':
foo.cc:14:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     for (int i = 0; i < arr.size(); i++)
      |                     ~~^~~~~~~~~~~~
foo.cc:24:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |         while (loc >= arr.size())
      |                ~~~~^~~~~~~~~~~~~

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