Alex Larson has an amount $X. She wants to distribute the amount among her N friends. Find the number of ways in which she can distribute this amount such that each friend gets at least $1. As the number of ways can be large so print it modulo 10 +7.   You have to complete the function count_ways that receives two integers X and N as arguments and returns the total number of ways.   Constraints 1 ≤ X ≤  10 1 ≤ N ≤  50   Note The order of distribution does not matter. If X=3 and N=2 then ﴾1, 2﴿ and ﴾2, 1﴿ are considered same.   Sample Input 0
6  3
Sample Output 0
3
Explanation X=6, N=3 There are 3 ways of distributing Rs 6  among 3 daughters, (1,1,4) ,(1,2,3) and (2,2,2).

Sample Input 1
10  5
Sample Output 1
7

 

 

 

solution
want one
I know it can be solved by (n+r-1)C(r-1) but i tried not able to get the desired output..

If anyone solved it please post the answer..

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