I would make a tree because there are not that many possibilities. to get 99 with numbers between 1 and 50 you have 50+49 and 49 and 50 nothing else will work because if one spin is less than 49 say 48 to get 99 you need 51 which is impossible. either you 50 then 49 or you get 49 then 50. the others are a bit harder because you need to find all possible spins that will sum to 52 which is a much larger number.
