For s ? (0+1)* let d(s) denote the decimal value of s(e.g.d(101)) = 5 Let L = {s ? (0+1)* d(s) mod 5=2 and d(s) mod 7 != 4} Which one of the following statements is true?
A)L is recursively enumerable, but not recursive
B)L is recursive, but not context-free
C)L is context-free, but not regular
D)L is regular

Question

Quizplus · Accepted Answer

L is regular because the conditions d(s) mod 5 = 2 and d(s) mod 7 != 4 can be determined by finite automata through state transitions that account for the remainder when divided by 5 and 7, respectively.

For S ? (0+1)* Let D(s) Denote the Decimal Value