/in/foo.cc: In function 'bool check(int, int)':
/in/foo.cc:10:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define ie(i,s,t) for(int i=s;i<=t;++i)
                                 
/in/foo.cc:40:5:
  ie(ii,0,node[t].size()-1)
     ~~~~~~~~~~~~~~~~~~~~~       
/in/foo.cc:40:2: note: in expansion of macro 'ie'
  ie(ii,0,node[t].size()-1)
  ^~
/in/foo.cc: In function 'int find(int, int)':
/in/foo.cc:10:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define ie(i,s,t) for(int i=s;i<=t;++i)
                                 
/in/foo.cc:51:5:
  ie(ii,0,node[t].size()-1)
     ~~~~~~~~~~~~~~~~~~~~~       
/in/foo.cc:51:2: note: in expansion of macro 'ie'
  ie(ii,0,node[t].size()-1)
  ^~
/in/foo.cc: In function 'void dp_spfa()':
/in/foo.cc:70:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int j=0;j<gra[x].size();++j)
                ~^~~~~~~~~~~~~~