Folder weigh-in

Report how much space each folder of a backup drive takes up, counting everything inside it at any depth.

The drive's file list has one string "path size" per file: a path of folder names and a file name joined by / (for example "src/app/main.py"), one space, and the size in bytes. Folder names never contain dots, and file names always do, so no path is both a file and a folder.

A file counts toward every folder above it: src/app/main.py adds its size to src/app and to src. Files directly in the root (no / in the path) belong to no folder.

If the same path is listed more than once, the file was saved again and only its last listing counts.

A folder is reported only if its total is greater than 0 and it sits at most depth levels down (src is level 1, src/app is level 2). Deeper files still count toward their reported ancestors.

Input: files, a list of strings in the format above, and depth, an integer of at least 1.

Output: a list of strings "folder total" with the folder path written without a trailing slash. Sort by total descending; equal totals are ordered by folder path in ordinary ascending string order. If no folder qualifies, return [].