Create and Query Hierarchical Path Values

### Problem Implement FileSystem. A valid path is one or more segments, each a slash followed by one or more lowercase letters; empty strings and `/` alone are not paths. createPath(path,value) succeeds only if the path is new and its parent already exists, returning whether it was created. Top-level paths may be created directly. get(path) returns the stored value or -1 if absent. ```cpp class FileSystem { public: FileSystem(); bool createPath(string path, int value); int get(string path); }; ``` ### Examples **Example 1:** ```text Input: construct FileSystem(); createPath("/box",7); createPath("/box/item",9); get("/box/item"); createPath("/box",3) Output: true,true,9,false Explanation: The child has an existing parent; the final duplicate cannot replace its value. ``` **Example 2:** ```text Input: construct FileSystem(); createPath("/a/b",2); get("/a"); createPath("/a",5) Output: false,-1,true Explanation: Missing parent /a blocks the child creation, but a top-level path can then be created. ``` ### Constraints - Each supplied path is valid, has length 2 to 100, and uses lowercase letters and slashes. - Values lie in `[1,1000000000]`. - At most 10000 total createPath/get calls occur. ### Contract considerations Keep the native constructor, createPath and get methods. The implicit root has no public stored value or query interface. ```hint Read the boundary condition Can a failed creation or a lookup of a missing path create any path or change an existing value? ``` ### Boundary reminders Keep the native constructor, createPath and get methods. The implicit root has no public stored value or query interface.