<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 {
public:
    int ans(vector<vector<int>> &v,int n){
        vector<vector<int>> vis(n,vector<int>(n,0));
        int sol=0;
        queue<pair<int,int>> q;
        vector<pair<int,int>> ind={{0,1},{1,0},{-1,0},{0,-1}};
        for(int i=0;i<n;i++){
            for(int j=0;j<n;j++){
                if(v[i][j]==1 && vis[i][j]!=1){
                    q.push({i,j});
                    vis[i][j]=1;
                    sol++;
                    while(!q.empty()){
                        auto temp=q.front();
                        q.pop();
                        int r=temp.first,c=temp.second;
                        for(int k=0;k<4;k++){
                            int newRow = r+ind[k].first;
                            int newCol = c+ind[k].second;
                            if(newRow>=0 && newRow<n && newCol>=0 && newCol<n && v[newRow][newCol]==1 && 
                            vis[newRow][newCol]!=1){
                                q.push({newRow,newCol});
                                vis[newRow][newCol]=1;
                            }
                        }
                    }
                }
            }
        }
        return sol;
    }
    int regionsBySlashes(vector<string>& grid) {
        int s=grid.size(),n=s*3;
        vector<vector<int>> v(n,vector<int> (n,1));
        for(int i=0;i<s;i++){
            for(int j=0;j<s;j++){
                if(grid[i][j]=='/'){
                    v[3*i][3*j+2]=0;v[3*i+1][3*j+1]=0;v[3*i+2][3*j]=0;
                }else if(grid[i][j]=='\\'){
                    v[3*i][3*j]=0;v[3*i+1][3*j+1]=0;v[3*i+2][3*j+2]=0;
                }
            }
        }
        for(int i=0;i<n;i++){
            for(int j=0;j<n;j++){
                cout << v[i][j] << " ";
            }
            cout << endl;
        }
        return ans(v,n);
    }
};
18648