foo.cc: In function 'int main()':
foo.cc:13:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(int j=0;j<n;j++)
  ^~~
foo.cc:15:3: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   return 0; 
   ^~~~~~
foo.cc: In function 'int toward(int*, int, int)':
foo.cc:19:6: warning: unused variable 'c' [-Wunused-variable]
  int c;
      ^
foo.cc:29:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^

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