foo.cc:20:1: error: extended character   is not valid in an identifier
   20 |  
      | ^
foo.cc: In function 'int main()':
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 < s1.length(); i++)
      |                     ~~^~~~~~~~~~~~~
foo.cc:12:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |         for (int j = 0; j < s2.length(); j++)
      |                         ~~^~~~~~~~~~~~~
foo.cc: At global scope:
foo.cc:20:1: error: '\U000000a0' does not name a type
   20 |  
      | ^

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