foo.cc: In function 'int read()':
foo.cc:9:15: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return y=='-'?-x:x;
         ~~~~~~^~~~~
foo.cc: In function 'int main()':
foo.cc:9:15: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return y=='-'?-x:x;
         ~~~~~~^~~~~
foo.cc:6:15: note: 'y' was declared here
  int x=0;char y;char o=getchar();
               ^
foo.cc:9:15: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return y=='-'?-x:x;
         ~~~~~~^~~~~
foo.cc:6:15: note: 'y' was declared here
  int x=0;char y;char o=getchar();
               ^
foo.cc:9:15: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
  return y=='-'?-x:x;
         ~~~~~~^~~~~
foo.cc:6:15: note: 'y' was declared here
  int x=0;char y;char o=getchar();
               ^

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

{"receive":"2020-05-23T07:08:10.854Z","handle":"2020-05-23T07:08:10.854Z","cache_start":"2020-05-23T07:08:10.860Z","read_cases":"2020-05-23T07:08:10.983Z","judge":"2020-05-23T07:08:10.988Z","done":"2020-05-23T07:08:12.555Z"}