<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:

        row_len = len(grid)
        col_len = len(grid)
        
        limits = set()
        adj_list = defaultdict(set)
        lands = set()

        count = 0

        for i in range(row_len):
            for j in range(col_len):
                baseRow = j*3
                baseCol = i*3

                val = grid[i][j]
                if( val == " "):
                    continue

                if(val == "/"):
                    limits.add((baseCol, baseRow+2))
                    limits.add((baseCol+1, baseRow+1))
                    limits.add((baseCol+2, baseRow))


                if(val == "\\"):
                    limits.add((baseCol, baseRow))
                    limits.add((baseCol+1, baseRow+1))
                    limits.add((baseCol+2, baseRow+2))
        

        for i in range(row_len*3):
            for j in range(col_len*3):
                if(i-1 >= 0):
                    adj_list[(i, j)].add((i-1, j))
                if(j-1 >= 0):
                    adj_list[(i, j)].add((i, j-1))
                if(i+1<row_len*3):
                    adj_list[(i,j)].add((i+1, j))
                if(j+1<col_len*3):
                    adj_list[(i,j)].add((i, j+1))


                if((i,j) not in limits):
                    lands.add((i, j))

        def bfs(start_node):
            queue = [start_node]

            while(queue):
                node = queue.pop(0)
                if(node in visited):
                    continue
                visited.add(node)

                for adjacent in adj_list[node]:
                    if(adjacent in limits):
                        continue

                    if(adjacent not in visited):
                        queue.append(adjacent)

        visited = set()

        for elem in lands:
            if(elem not in visited):
                bfs(elem)
                count += 1

        return count
23105