Bug Report for foreign-dictionary (C#).

[Samermadieh]

Bug Report for https://neetcode.io/problems/foreign-dictionary

Two issues:

1. Using the '$' character causes compiler errors.
2. Using C# in general, the error line is always displayed as 4 lines ahead of the actual line where the problem is. So if problem is at line 16, it will show as line 20.

I declared: char prev = '$';

Threw compiler errors:
Main.cs(20,29): error CS1010: Newline in constant
Main.cs(20,29): error CS1011: Empty character literal
etc... (cascading)

Changed that to: char prev = '@';
Worked fine.