I need to find DFA (or NFA, $\epsilon$-NFA, it's not improtant (I know how to convert between them)) that accept all strings of $0$'s and $1$'s such that every block of five consecutive symbols contains at least two $0$'s.
This is exercise 2.5 c) from Hopcroft's Introduction to Automata Theory.
If someone could also explain and help to build regular expresion from this (I'm still learning)?
Hint: Try the opposite: find DFA that accepts all strings of 0's and 1's such that there exists a block of five consecutive symbols containing one or zero 0's. And then build the complement to this DFA.
Added: There was a typo: "every block" -> "there exists a block". Sorry.