When I run the code in windows, it works as expected. But when I run it in linux, the program doesn't run as expected and produces a completely different output.
I'm assuming its a problem in the all_unique_letters method, but I can't seem to figure it out.
bool all_unique_letters(const string &s),
unsigned int v; is used without being initialized. If it contains something else that
0, the function reports a letter as a duplicate when it is not.