Compute board-game score from regions

You are given a 2D board for a board game. Each cell is encoded like `G1` or `W0`: - The first character is the **terrain/area type** (e.g., `G`, `W`, `S`). - The digit is the number of **crowns** in that cell (0–9). Two cells belong to the same **area/region** if they have the same terrain type and are connected by 4-directional adjacency (up/down/left/right). For each region: \[ \text{regionScore} = (\#\text{cells in region}) \times (\text{sum of crowns in region}) \] Return the **total score** across all regions. ### Example Board (rows): 1. `G1, G2, W0, W1, S1` 2. `G2, G3, W0, W1, S1` 3. `S2, S3, S1, G1, S1` 4. `G1, G2, W0, W1, S1` 5. `G1, G2, W0, W1, S1` Compute the total score for this board. ### Additional requirement Write a small set of self-contained test cases that cover edge cases (e.g., all same terrain, all crowns 0, single-cell regions, multiple disjoint regions of same terrain type).