foo.cc:4:10: error: stray '\357' in program
     int a，b;
          ^
foo.cc:4:11: error: stray '\274' in program
     int a，b;
           ^
foo.cc:4:12: error: stray '\214' in program
     int a，b;
            ^
foo.cc: In function 'int main()':
foo.cc:4:13: error: expected initializer before 'b'
     int a，b;
             ^
foo.cc:5:10: error: 'a' was not declared in this scope
     cin>>a>>b;
          ^
foo.cc:5:13: error: 'b' was not declared in this scope
     cin>>a>>b;
             ^

自豪的采用 HydroJudge 进行评测(github.com/hydro-dev/HydroJudge)