1232. Check If It Is a Straight Line-缀点成线

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 in python:

class Solution:
    def checkStraightLine(self, coordinates: List[List[int]]) -> bool:
        if len(coordinates) <= 2:
            return True
        for i in range(2, len(coordinates)):
            if (coordinates[i][1]-coordinates[i-2][1])*(coordinates[i-1][0]-coordinates[i-2][0]) != (coordinates[i][0]-coordinates[i-2][0])*(coordinates[i-1][1]-coordinates[i-2][1]):
                return False
        return True