Problem Statement
You are given a tree with one node painted as black and rest all are colored as white.You can paint any white node as black if its parent is colored as black.
Determine the count of the unique coloring of the tree.
Note: the count should be returned mod(10^9+1)

Example
input : N=3,blackNode=1,edges=[[1,2],[1,3]]
output : 4

input : N=6,blackNode=1,edges=[[1,2],[2,3],[2,4],[4,5],[4,6]]
output : 11
The exam is finished but still the question is running in my mind,can anyone suggest me the approach