rying to solve a coding problem here is the text:

input : the first line of the input consists of 4 space separated integers - N (denoting the number of players), M (denoting the number of passes), and X and Y, denoting ThunderCracker's and Munkee's numbers respectively. The next line contains M space separated integers, denoting array A, the power with which passes can be made in the i'th pass (1<= i <= M)

Output: A single integer, that is the number of ways in which the ball can be passed such that the first pass is made by ThunderCracker, and the ball reaches MunKee after M passes. As answer can be very large, output it modulo 100000007

Constaraints:

2 <= N <= 2000 1 <= M <= 2000 1 <= Ai <= 1000 1 <= X, Y <= N

It guaranted that X and Y are distinct integers

can someone give me a hint?