As you have known MMM corporation lab researches the matter of haricot proportions in soup For every day. The ladle is placed down into the soup pan. This ladle holds exactly M haricot seeds of N got into the pan. All the seeds are of different size.
Experimenters calculate the quantity of possible methods to proportion M seeds in the pan with the formula: C = N! / (M! · (N − M)!). The main feature of these experiments is the quantity of different prime divisors of number C.
Lest money would be spent for programmer, MMM corporation board decided to make necessary estimating during the ICPC quarterfinal in Rybinsk. Thus, your aim is to find this quantity.
The only line contains integers N and M that are the number of haricot seeds in the pan and the capacity of the ladle (1 ≤ M < N ≤ 50000).
Output the quantity of different prime divisors of number C.
In the example C = 5! / (3! · 2!) = 120 / (6 · 2) = 10 = 2 · 5.
Problem Source: Rybinsk State Avia Academy