foo.cc: In function 'int main()':
foo.cc:11:2: error: expected ';' before 'for'
  for(i=0;i<n;i++)
  ^~~
foo.cc:11:11: warning: statement has no effect [-Wunused-value]
  for(i=0;i<n;i++)
          ~^~
foo.cc:11:17: error: expected ';' before ')' token
  for(i=0;i<n;i++)
                 ^

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