{1}{2}{4}{5}{10}{20}{1,2}{1,4}{1,5}{1,10}{1,20}{2,4}{2,5}{2,10}{2,20}{4,5}{4,10}{4,20}{5,10}{5,20}{1,2,4}{1,2,5}{1,2,10}{1,2,20}{2,4,5}{2,4,10}...
당신은 어느 그룹입니까?