Check If It Is a Straight Line Solutions in C++

/// Source : https://leetcode.com/problems/check-if-it-is-a-straight-line/
/// Author : liuyubobobo
/// Time   : 2019-10-19

#include <iostream>
#include <vector>

using namespace std;


/// Linear Scan
/// Time Complexity: O(n)
/// Space Complexity: O(1)
class Solution {
public:
    bool checkStraightLine(vector<vector<int>>& coordinates) {

        int a = coordinates[1][1] - coordinates[0][1];
        int b = coordinates[1][0] - coordinates[0][0];
        for(int i = 2; i < coordinates.size(); i ++){
            int y = coordinates[i][1] - coordinates[0][1];
            int x = coordinates[i][0] - coordinates[0][0];
            if(y * b != x * a) return false;
        }
        return true;
    }
};


int main() {

    return 0;
}