Unique Substrings

Teddy and Freddy are two friends. Teddy has a pile of strings of size $N$. Each string $Si$ in the pile has length less or equal to $100$ ($len(Si) \leq 100$). Teddy and Freddy like playing with strings. Teddy gives Freddy a string $B$ of size $M$. Teddy and Freddy like playing with strings. Teddy gives Freddy a string $B$ of size $M$. He asks Freddy to find the count of the unique substri