<p>An <code>n x n</code> grid is composed of <code>1 x 1</code> squares where each <code>1 x 1</code> square consists of a <code>&#39;/&#39;</code>, <code>&#39;\&#39;</code>, or blank space <code>&#39; &#39;</code>. These characters divide the square into contiguous regions.</p>

<p>Given the grid <code>grid</code> represented as a string array, return <em>the number of regions</em>.</p>

<p>Note that backslash characters are escaped, so a <code>&#39;\&#39;</code> is represented as <code>&#39;\\&#39;</code>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2018/12/15/1.png" style="width: 200px; height: 200px;" />
<pre>
<strong>Input:</strong> grid = [&quot; /&quot;,&quot;/ &quot;]
<strong>Output:</strong> 2
</pre>

<p><strong class="example">Example 2:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2018/12/15/2.png" style="width: 200px; height: 198px;" />
<pre>
<strong>Input:</strong> grid = [&quot; /&quot;,&quot;  &quot;]
<strong>Output:</strong> 1
</pre>

<p><strong class="example">Example 3:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2018/12/15/4.png" style="width: 200px; height: 200px;" />
<pre>
<strong>Input:</strong> grid = [&quot;/\\&quot;,&quot;\\/&quot;]
<strong>Output:</strong> 5
<strong>Explanation: </strong>Recall that because \ characters are escaped, &quot;\\/&quot; refers to \/, and &quot;/\\&quot; refers to /\.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>n == grid.length == grid[i].length</code></li>
	<li><code>1 &lt;= n &lt;= 30</code></li>
	<li><code>grid[i][j]</code> is either <code>&#39;/&#39;</code>, <code>&#39;\&#39;</code>, or <code>&#39; &#39;</code>.</li>
</ul>

class Solution:
    def regionsBySlashes(self, grid: List[str]) -> int:
        def dfs(x, y):
            if x < 0 or y < 0 or x >= 3 * n or y >= 3 * n or (x, y) in visit or board[x][y] == 1:
                return
            
            visit.add((x, y))
            for dx, dy in [[0, 1], [1, 0], [0, -1], [-1, 0]]:
                dfs(dx + x, dy + y)
            
        visit = set() 
        n = len(grid)
        result = 0
        board = [[0] * 3 * n for i in range(n * 3)]
        for i in range(n):
            for j in range(n):
                if grid[i][j] == "/":
                    board[i*3][j*3 + 2] = board[i*3 + 1][j*3 + 1] = board[i*3 + 2][j*3] = 1
                elif grid[i][j] == "\\":
                    board[i*3][j*3] = board[i*3 + 1][j*3 + 1] = board[i*3 + 2][j*3 + 2] = 1

        for i in range(n * 3):
            for j in range(n * 3):
                if board[i][j] == 0 and (i, j) not in visit:
                    dfs(i, j)
                    result += 1
        
        return result

        # def dfs(x, y):
        #     if x < 0 or y < 0 or x >= 3*n or y >= 3*n or (x, y) in visit or g[x][y] == 1:
        #         return

        #     visit.add((x, y))
        #     for dx, dy in [[0, 1], [1, 0], [0, -1], [-1, 0]]:
        #         dfs(dx + x, dy + y)
            
        
        # result = 0
        # n = len(grid)
        # g = [[0] * 3 * n for i in range (3 * n)] 
        # visit = set()

        # for i in range(n):
        #     for j in range(n):
        #         if grid[i][j] == "/":
        #             g[i*3][j*3 + 2] = g[i*3 + 1][j*3 + 1] = g[i*3 + 2][j*3] = 1
        #         elif grid[i][j] == "\\":
        #             g[i*3][j*3] = g[i*3 + 1][j*3 + 1] = g[i*3 + 2][j*3 + 2] = 1
        # print(g)
        # for i in range(n*3):
        #     for j in range(n*3):
        #         if g[i][j] == 0 and (i, j) not in visit:
        #             dfs(i, j)
        #             result += 1
                    
        # return result

            



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