foo.cc: In function 'int main()':
foo.cc:14:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(i=0;i<line.length();i++)
           ^
foo.cc:23:7: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(i==line.length()-1)
       ^

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

{"receive":"2020-04-05T08:56:48.749Z","handle":"2020-04-05T08:56:48.749Z","cache_start":"2020-04-05T08:56:48.757Z","read_cases":"2020-04-05T08:56:48.887Z","judge":"2020-04-05T08:56:48.889Z","done":"2020-04-05T08:56:49.777Z"}