Regions Cut By Slashes

An `n x n` grid is composed of `1 x 1` squares where each `1 x 1` square consists of a `'/'`, `'\'`, or blank space `' '`. These characters divide the square into contiguous regions. Given the grid `grid` represented as a string array, return _the number of regions_. Note that backslash characters are escaped, so a `'\'` is represented as `'\\'`.   **Example 1:** **Input:** grid = [" /","/ "] **Output:** 2 ``` **Example 2:** **Input:** grid = [" /"," "] **Output:** 1 ``` **Example 3:** **Input:** grid = ["/\\","\\/"] **Output:** 5 **Explanation: **Recall that because \ characters are escaped, "\\/" refers to \/, and "/\\" refers to /\. ```   **Constraints:** - `n == grid.length == grid[i].length` - `1 <= n <= 30` - `grid[i][j]` is either `'/'`, `'\'`, or `' '`.