Solution Explanation:

This problem asks to find the maximum number of enemies that can be killed by placing a bomb in an empty cell of a grid. The bomb kills all enemies in the same row and column until it hits a wall.

The solution uses a straightforward approach:

1. Preprocessing: We create a new grid g of the same dimensions as the input grid grid. Each cell g[i][j] will store the total number of enemies that would be killed if a bomb were placed at grid[i][j].

2. Row-wise and Column-wise Enemy Counting: We iterate through the grid twice for each row and column. The first pass counts enemies from left to right (or top to bottom). The second pass counts enemies from right to left (or bottom to top). This ensures that we correctly count all enemies affected by a bomb placed at any position. Whenever a 'W' (wall) is encountered, the counter resets to 0.

3. Aggregation: The value in g[i][j] after these iterations represents the total number of enemies killed in row i and column j.

4. Finding the Maximum: Finally, we iterate through g, considering only cells where grid[i][j] is '0' (empty). We find the maximum value in g among these cells, representing the maximum number of enemies that can be killed.

Time and Space Complexity Analysis:

• Time Complexity: O(mn), where 'm' and 'n' are the dimensions of the grid. We iterate through the grid four times (twice for rows and twice for columns) in the preprocessing steps. Finding the maximum takes another O(mn) iteration, but this is dominated by the preprocessing steps.

• Space Complexity: O(m*n). We use an auxiliary grid g of the same size as the input grid to store the counts of killed enemies.

Code Explanation (Python):

The Python code directly implements the algorithm described above. The maxKilledEnemies function takes the input grid and returns the maximum number of enemies that can be killed. The code is well-commented to explain each step.

Code Explanation (Other Languages):

The Java, C++, and Go code implementations are functionally equivalent to the Python solution. They follow the same algorithm, with minor syntactic differences specific to each language. The core logic of iterating over rows and columns and counting enemies remains consistent across all implementations.