Design File System

Core idea: A path like /leet/code is not a string — it's a sequence of components ["leet", "code"]. Store those components in a trie where each edge is one component name (not one character), and the structure itself encodes the parent/child relationship that createPath has to validate.

Problem, rephrased

Imagine you're building the directory layer of a tiny in-memory virtual file system. People hand you absolute paths — strings of the form / followed by one or more lowercase-letter segments, e.g. /leetcode or /leetcode/problems — and ask you to remember a value at each path. You support exactly two operations:

• createPath(path, value) — create the path and attach value to it. Return True on success. Return False if the path already exists, or if its parent path doesn't exist yet. (You can't create /a/b until /a is already there.)
• get(path) — return the value stored at path, or -1 if no such path exists.

The empty string "" and the bare "/" are not valid paths.

This is LeetCode 1166 — Design File System.