/in/foo.cc: In function 'int main()':
/in/foo.cc:8:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 |         for(int i=0;i<s.size();i++)
      |                     ~^~~~~~~~~
/in/foo.cc:10:22: 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<str.size();i++)
      |                     ~^~~~~~~~~~~
/in/foo.cc:15:35: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   15 |                 if(str[fir-1]==' '&&str[fir+s.size()]==' '||//中间
/in/foo.cc:17:32: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   17 |                 str[fir-1]==' '&&fir+s.size()==str.size())  //结尾