foo.cc: In function 'int main()':
foo.cc:11:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |         for (int i = 0; i < s.size(); i++) {
      |                         ~~^~~~~~~~~~
foo.cc:24:5: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
   24 |     else
      |     ^~~~
foo.cc:26:9: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'else'
   26 |         return 0;
      |         ^~~~~~

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