(a) Find the number of ways that Magnus can give out 12 identical stickers to 12 of his friends. (Not everyone has to get a sticker.)
(b) Find the number of ways that Magnus can give out 12 identical stickers to 12 of his friends, if every friend gets at least one sticker.
For the second part, it's 12!, which is 12*11*10*...*2*1, which is 479,001,600