运行 ID: 40050

Main.cc: In function ‘int main()’:
Main.cc:17:9: error: redeclaration of ‘std::__cxx11::string s1’
  string s1 = change(s1);
         ^~
Main.cc:14:9: note: ‘std::__cxx11::string s1’ previously declared here
  string s1, s2;
         ^~
Main.cc:18:9: error: redeclaration of ‘std::__cxx11::string s2’
  string s2 = change(s2);
         ^~
Main.cc:14:13: note: ‘std::__cxx11::string s2’ previously declared here
  string s1, s2;
             ^~