In a file system where both directories and files are stored, we are given a string representation of the system. The string includes the directory structure, with tab characters (’\t’) representing subdirectories and newline characters (’\n’) representing file and directory boundaries. Each directory and file has a unique absolute path. Compute the length of the longest absolute path to a file. If no file exists, return 0.
Given two strings s and t, return true if s is a subsequence of t, or false otherwise. A subsequence is formed by deleting some characters of t while maintaining the relative order of the remaining characters.
You are given a string that is encoded using the pattern k[encoded_string], where the substring inside the square brackets is repeated exactly k times. Your task is to decode the string by expanding it according to the given encoding rule.
Given a string s and an integer k, return the length of the longest substring of s such that the frequency of each character in this substring is greater than or equal to k. If no such substring exists, return 0.
