/** * Definition for a point. * struct Point { *     int x; *     int y; *     Point() : x(0), y(0) {} *     Point(int a, int b) : x(a), y(b) {} * }; */class Solution {public:    int maxPoints(vector<Point> &points) {        int n = points.size(); //number of the points        if (n<=2){return n;}           vector<double> k; //vector to store the slops for one point with all the other points        int res = 0;                 for (int i=0;i<n;i++){ // for each point in the 2d plane            k.clear();            int dup = 1; // number of the duplicates with currrent point            for (int j=0;j<n;j++){                 if (i!=j){ // for every other point                    if (points[i].x-points[j].x==0){ // if the slope is a vertical line                        if (points[i].y-points[j].y==0){ // if the point j is the same as point i                            dup++;                          }else{                            k.push_back(99999); //store the vertical line to a specific slope                        }                    }else{ // if it is the regular slop between point i and j                        k.push_back(10000*(points[i].y-points[j].y)/(points[i].x-points[j].x)); // store the slope                    }                }            }                         sort(k.begin(),k.end()); //sort the slopes for counting                         int pp = 1; //number of points in the same line of the point i            if (k.size()==0){pp=0;}              for (int jj=1;jj<k.size();jj++){ //count pp                if (k[jj]==k[jj-1]){                    pp++;                }else{                    if (pp+dup>res){res=pp+dup;} // res = pp + the number of duplicates                    pp = 1;                }            }            if (pp+dup>res){res = pp+dup;}        }         return res;    }};