You have 4 independent coding tasks. ## 1) Uppercase vs lowercase count difference Given a string `s` consisting of ASCII letters (and possibly other characters), count: - `U` = number of uppercase letters `'A'..'Z'` - `L` = number of lowercase letters `'a'..'z'` Return the absolute difference `|U - L|`. **Input:** string `s` **Output:** integer --- ## 2) Scooter-walking trip (total distance ridden) You travel along a 1D line from position `0` to position `target > 0`. There are scooters located at positions given by an array `scooters` (not necessarily sorted). Each scooter can be ridden for **up to 10 distance units** and then becomes unusable. Rules of movement: 1. You start at position `pos = 0`. 2. If there exists a scooter at a position `>= pos` and `<= target`, you **walk** to the closest scooter on your right (i.e., the smallest scooter position `p` such that `p >= pos`). 3. From that scooter position `p`, you **ride** it forward for `min(10, target - p)` distance units, ending at `pos = p + min(10, target - p)`. 4. Repeat steps 2–3 until you reach `target` or there is no scooter at or ahead of your current position before `target`. If no such scooter exists, you walk the remaining distance to `target`. Return the **total distance traveled while riding scooters** (do not include walking distance). **Input:** integer `target`, integer array `scooters` **Output:** integer total ridden distance --- ## 3) Apply operations to a matrix Given an `m x n` matrix `A` and a list of operations, apply them in order and return the final matrix. Supported operations: - `SWAP_ROW r1 r2`: swap row `r1` and row `r2` - `SWAP_COL c1 c2`: swap column `c1` and column `c2` - `REVERSE_ROW r`: reverse the elements within row `r` (e.g., `[1,2,3] -> [3,2,1]`) - `REVERSE_COL c`: reverse the elements within column `c` - `ROTATE_CW`: rotate the entire matrix 90 degrees clockwise (dimensions become `n x m`) Assume indices are 0-based and all operations are valid. **Input:** matrix `A`, list of operations (with parameters) **Output:** final matrix after all operations --- ## 4) Reconstruct travel path from unordered adjacent photos You forgot the exact travel order, but you have `n-1` photos. Each photo records two **consecutive** locations you visited, but **the order within a photo is unknown**. Example: `[[1,2],[3,2],[4,3]]` corresponds to the path `[1,2,3,4]` (or the reverse `[4,3,2,1]`). Given an array `photos` of length `n-1`, where each element is a pair `[a, b]` representing an undirected adjacency between consecutive locations, reconstruct and return the full path as an array of length `n`. You may return the path in either direction. **Input:** array `photos` of pairs **Output:** array `path` listing all locations in order **Assumptions:** The underlying graph formed by the pairs is guaranteed to be a simple path (i.e., exactly two endpoints with degree 1, all others degree 2).