foo.cc: In function 'int main()':
foo.cc:10:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
10 | for (int i = 0; i < a.size(); i++)
| ~~^~~~~~~~~~
foo.cc:14:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
14 | for (int i = 0; i < b.size(); i++)
| ~~^~~~~~~~~~
foo.cc:28:7: warning: unused variable 'x' [-Wunused-variable]
28 | int x = -1;
| ^
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