Hey, I’ve got problem. I have 2 strings and I want to delete the first occurring of characters from str1 which are in str2. For example:

- Str1: show

Str2: slow

Output: h- Str1: expensive

Str2: terrible

Output: xpnsve

I used find_first_of() function to solve this problem, but in practice it turned out too slow. Is there any faster way to solve this problem? Please, help :)