Day 8 Check If It Is a Straight Line.cpp

PROBLEM:


You are given an array coordinates, coordinates[i] = [x, y], where [x, y] represents the coordinate of a point.
Check if these points make a straight line in the XY plane.

Example 1:
Input: coordinates = [[1,2],[2,3],[3,4],[4,5],[5,6],[6,7]]
Output: true

Example 2:
Input: coordinates = [[1,1],[2,2],[3,4],[4,5],[5,6],[7,7]]
Output: false
 

Constraints:

2 <= coordinates.length <= 1000
coordinates[i].length == 2
-10^4 <= coordinates[i][0], coordinates[i][1] <= 10^4
coordinates contains no duplicate point.



SOLUTION:



class Solution {
public:
    bool checkStraightLine(vector<vector<int>>& coordinates) {
        int n=coordinates.size();
        int m=2,i;
        
        if(n<3)
        {
            return true;
        }
        
        for(i=0;i+2<n;i++)
        {   
            if( (coordinates[i+1][0]-coordinates[i][0])*(coordinates[i+2][1]-coordinates[i+1][1]) ==                           (coordinates[i+2][0]-coordinates[i+1][0])*(coordinates[i+1][1]-coordinates[i][1])  ) 
            {
                continue;
            }
            else
                return false;
        }
        
        return true;
    }
};