<p>Given an array of <code>points</code> where <code>points[i] = [x<sub>i</sub>, y<sub>i</sub>]</code> represents a point on the <strong>X-Y</strong> plane, return <em>the maximum number of points that lie on the same straight line</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/02/25/plane1.jpg" style="width: 300px; height: 294px;" />
<pre>
<strong>Input:</strong> points = [[1,1],[2,2],[3,3]]
<strong>Output:</strong> 3
</pre>

<p><strong class="example">Example 2:</strong></p>
<img alt="" src="https://assets.leetcode.com/uploads/2021/02/25/plane2.jpg" style="width: 300px; height: 294px;" />
<pre>
<strong>Input:</strong> points = [[1,1],[3,2],[5,3],[4,1],[2,3],[1,4]]
<strong>Output:</strong> 4
</pre>

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

<ul>
	<li><code>1 &lt;= points.length &lt;= 300</code></li>
	<li><code>points[i].length == 2</code></li>
	<li><code>-10<sup>4</sup> &lt;= x<sub>i</sub>, y<sub>i</sub> &lt;= 10<sup>4</sup></code></li>
	<li>All the <code>points</code> are <strong>unique</strong>.</li>
</ul>

class Solution {
public:
    int maxPoints(vector<vector<int>>& points) {

        unordered_map< int,unordered_map< double,unordered_set<double>> > b;
        unordered_map<double,unordered_map<double,int>> c;

        int n=points.size(),max=2;
        double k,m;
        if (n==1) return 1;
        for (int i=0;i<n-1;i++){
            for(int j=i+1;j<n;j++){
                if (points[i][0]==points[j][0]) k=2147483647;
                else {
                    k=(points[i][1]-points[j][1]);
                    k/=(points[i][0]-points[j][0]);
                }
                if (k==2147483647){
                    m=points[i][0];
                }else m=points[i][1]-k*points[i][0];

                if (b.find(i)==b.end() || b[i].find(k)==b[i].end() || !b[i][k].contains(m)){
                    b[i][k].insert(m);
                    if (c.find(k)==c.end() || c[k].find(m)==c[k].end()){
                        c[k][m]=1;
                    }else{ 
                        c[k][m]++;
                        if (max<c[k][m]) max=c[k][m];
                    }
                } 

                if (b.find(j)==b.end() || b[j].find(k)==b[i].end() || !b[j][k].contains(m)){
                    b[j][k].insert(m);
                    if (c.find(k)==c.end() || c[k].find(m)==c[k].end()){
                        c[k][m]=1;
                    }else{ 
                        c[k][m]++;
                        if (max<c[k][m]) max=c[k][m];
                    }
                } 

            }
        }
        return max;
    }
};
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