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 "\\" in the input.
Example 1:
Input: grid = [" /","/ "]
Output: 2
Explanation: The 2x2 grid with two / characters creates 2 regions.
Example 2:
Input: grid = [" /"," "]
Output: 1
Explanation: The single / does not fully partition the grid.
Example 3:
Input: grid = ["/\\","\\/"]
Output: 5
Explanation: The grid forms a diamond pattern with 5 separate regions.
n == grid.length == grid[i].length1 <= n <= 30grid[i][j] is '/', '\', or ' '