This is my CPP solution.
class Solution {
public:
bool checkStraightLine(vector<vector<int>>& coordinates) {
int n = coordinates.size();
if(n == 2)
return true;
vector<int> l_point = {coordinates[1][0], coordinates[1][1], coordinates[0][0], coordinates[0][1]};
for(int i=2;i<n;i++){
if((coordinates[i][1] - l_point[1])*(l_point[0] - l_point[2]) != (coordinates[i][0] - l_point[0])*(l_point[1] - l_point[3]))
return false;
}
return true;
}
};