foo.cc: In function 'void get_maxd(long long int, long long int)':
foo.cc:14:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<vec[id].size();i++)
              ~^~~~~~~~~~~~~~~
foo.cc: In function 'void get_dfn(long long int, long long int, long long int)':
foo.cc:28:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<vec[id].size();i++)
              ~^~~~~~~~~~~~~~~
foo.cc: In function 'void solve(long long int, long long int)':
foo.cc:45:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<vec[id].size();i++)
              ~^~~~~~~~~~~~~~~
foo.cc:58:8: warning: unused variable 'afa' [-Wunused-variable]
    int afa=0;
        ^~~

自豪的采用jd5进行评测(github.com/masnn/jd5)