You are given a string $$$s$$$ with length $$$N$$$ and in this problem you should find the number of unique subsequences (not substrings) of the string of every length. eg. find the number of unique subsequences of length $$$1,$$$ then length $$$2, 3 ... N$$$. Answer can be big so print it modulo $$$1e9+7$$$. If the statement is confusing please, see the "explanations" below. I found this post on geeksforgeeks but it counts the total number of distinct subsequences.
Length of the string $$$N<=1000$$$
Example:
Input:
$$$s = dpdp$$$
Output:
$$$2$$$ $$$4$$$ $$$4$$$ $$$1$$$
Explanation:
there are two subsequences of length 1: $$${d, p}$$$
4 subsequences of length 2: $$${dp, dd, pd, pp}$$$
4 subsequences of length 3: $$${dpd, pdp, dpp, ddp}$$$
1 subsequence of length 4: $$${dpdp}$$$
I think it's very easy problem but I have no idea how to solve it. Thanks in advance.
Sorry for my poor English.