foo.cc: In function 'std::vector<int> find(const std::string&)':
foo.cc:9:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |     for (int i = 0; i < str.length(); i++)
      |                     ~~^~~~~~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:59:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |             for (int i = 0; i < mistake.size(); ++i)
      |                             ~~^~~~~~~~~~~~~~~~

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