Hi , HappyNewYear ;)

I saw some problem that need hashing to solve , Such as 271D - Good Substrings and 127D - Password .

So I decided to learn this data structure !

I tried to find it by google but I can't find any intelligible tutorial .

Can anyone help me with any helpful tutorial ?!

Hi :)

Can any body help me about problem 299 sgu !?

Why my code got Runtime Error on test 11 !! ?

What's wrong with me ?!