<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:
    void make(int i,int j,vector<vector<int>>&grid){
        int low=i*3;
        int high=3*(i+1);
        int low1=j*3;
        int high1=3*(j+1);
        int t=0;
        for(int k=low;k<high;k++){
            grid[low1+t][k]=1;
            t++;
        }
        return;
    }
    void make2(int i,int j,vector<vector<int>>&grid){
        int low=i*3;
        int high=3*(i+1);
        int low1=j*3;
        int high1=3*(j+1);
        int t=0;
        for(int k=high-1;k>=low;k--){
            grid[low1+t][k]=1;
            t++;
        }
        return;
    }
    void dfs(int i,int j,vector<vector<int>>&vis,vector<vector<int>>&g){
        int n=vis.size();
        if(i<0||i>=n||j<0||j>=n||vis[i][j]||g[i][j]) return;
        vis[i][j]=1;
        int dir[4][2]={{0,1},{1,0},{-1,0},{0,-1}};
        for(int k=0;k<4;k++){
            int nr=i+dir[k][0];
            int nc=j+dir[k][1];
            dfs(nr,nc,vis,g);
        }
        return;
    }
    int regionsBySlashes(vector<string>& grid) {
        int l=0;
        int n=grid.size();
        vector<vector<int>>g(n*3,vector<int>(n*3,0));
        for(int j=0;j<n;j++){
            string s=grid[j];
            for(int i=0;i<s.size();i++){
                if(s[i]=='\\'){
                    cout<<i<<endl;
                    make(i,j,g);
                }
                if(s[i]=='/'){
                    make2(i,j,g);
                }
            }
        }
        for(auto it:g){
            for(int x:it){
                cout<<x;
            }
            cout<<endl;
        }
        int m=g.size();
        vector<vector<int>>vis(m,vector<int>(m,0));
        int ans=0;
        for(int i=0;i<m;i++){
            for(int j=0;j<m;j++){
                if(!vis[i][j]&&g[i][j]!=1){
                    ans++;
                    dfs(i,j,vis,g);
                }
            }
        }
        return ans;
    }
};
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