Check Validity of Input String

Valid Dot-Letter String Easy · Topics · Company Tags · Hints You are given a string s made up only of lowercase English letters and the period character '.'. Return true if the string is valid; otherwise return false. A valid string must have every maximal block of one or more periods placed between letters: there must be at least one lowercase letter immediately before the block and at least one lowercase letter immediately after it. Equivalently, the string cannot begin or…