1 program Project1; 2 var 3   n, p, tc: longint; 4   map: array[0..1000,0..1000] of boolean; 5   b: array[0..1000] of boolean; 6   link: array[0..1000] of longint; 7  8 procedure init; 9 var10   i, j, t, y: longint;11 begin12   readln(p,n);13   fillchar(map,sizeof(map),false);14   for i := 1 to p do15     begin16       read(t);17       for j := 1 to t do18         begin19           read(y);20           map[i,p+y] := true;21           map[p+y,i] := true;22           //writeln(i,'',y);23         end;24     end;25  { for i := 1 to n+p do26     for j := 1 to n+p do writeln(i,' ',j,' ',map[i,j]); }27 end;28 29 function dfs(k: longint):boolean;30 var31   i: longint;32 begin33   for i := 1 to n+p do34     if (map[k,i]) and (not b[i]) then35       begin36         b[i] := true;37         if (link[i] = 0) or (dfs(link[i])) then38           begin39             link[i] := k;40             exit(true);41           end;42       end;43   exit(false);44 end;45 46 procedure work;47 var48   i, max: longint;49 begin50   fillchar(link,sizeof(link),0);51   max := 0;52   for i := 1 to p do53     begin54       fillchar(b,sizeof(b),false);55       if dfs(i) then inc(max);56     end;57 //  writeln(max);58 //  for i := 1 to n do write(link[i],'');59   if max = p then writeln('YES') else writeln('NO');60 end;61 62 begin63   readln(tc);64   while tc > 0 do65     begin66       init;67       work;68       dec(tc);69     end;70 end.