/in/foo.cc: In function 'int main()':
/in/foo.cc:13:15: warning: iteration 999999 invokes undefined behavior [-Waggressive-loop-optimizations]
      if(Rong[i])
         ~~~~~~^
/in/foo.cc:3:31: note: within this loop
 #define go(a,i,n) for(ll i=a;i<=n;i++)
                                
/in/foo.cc:12:7:
  go(2,i,N)
       ~~~                      
/in/foo.cc:12:2: note: in expansion of macro 'go'
  go(2,i,N)
  ^~