You are given an array A of size N. A special number of a subsequence S is a number formed by the concatenation of all the elements of the subsequence S.
Find the count of non-empty subsequences of A having their special number divisible by X and of length K. Since the answer can be huge, output it modulo 10^9+7
I dont know How to start this Plzz help??
Constraint:- 1 <= T <= 10 1 <= N <= 10^3 2 <= X <= 20 1 <= A[i] < 1000 1 <= K <= 100