Subtract 12 from 2009, the remaining 13, the remaining 14, the remaining 15, and so on, until you subtract the remaining 12009______ .

Subtract 12 from 2009, the remaining 13, the remaining 14, the remaining 15, and so on, until you subtract the remaining 12009______ .

∵ 2009 subtracts its 12 to get 2009 × 12, then subtracts the remaining 13 to get 2009 × 12-2009 × 12 × 13, that is, 2009 × 12 × 23, and so on, until finally subtracts the remaining 12009 to get 2009 × 12 × 23 × 34 × X 20082009 = 1, so the answer is 1