foo.cc: In function 'int dp(int)':
foo.cc:17:7: warning: unused variable 'index' [-Wunused-variable]
   int index = 0;
       ^~~~~
foo.cc: In function 'int main()':
foo.cc:40:21: warning: 'memset' used with length equal to number of elements without multiplication by element size [-Wmemset-elt-size]
   memset(dir,0,MAX_N);
                     ^

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

{"receive":"2020-07-23T14:09:02.671Z","handle":"2020-07-23T14:09:02.671Z","cache_start":"2020-07-23T14:09:02.677Z","read_cases":"2020-07-23T14:09:02.810Z","judge":"2020-07-23T14:09:02.812Z","done":"2020-07-23T14:09:05.239Z"}