[Solved] On a 2D plane, there are n points with integer coordinates points[i] = [xi, yi]. Return the minimum time in seconds to visit all the points in the order given by points.

Table of Contents

Question

On a 2D plane, there are n points with integer coordinates points[i] = [xi, yi]. Return the minimum time in seconds to visit all the points in the order given by points.

You can move according to these rules:

  • In 1 second, you can either:
    • move vertically by one unit,
    • move horizontally by one unit, or
    • move diagonally sqrt(2) units (in other words, move one unit vertically then one unit horizontally in 1 second).
  • You have to visit the points in the same order as they appear in the array.
  • You are allowed to pass through points that appear later in the order, but these do not count as visits.

Example 1:

Input: points = [[1,1],[3,4],[-1,0]]
Output: 7
Explanation: One optimal path is [1,1] -> [2,2] -> [3,3] -> [3,4] -> [2,3] -> [1,2] -> [0,1] -> [-1,0]   
Time from [1,1] to [3,4] = 3 seconds 
Time from [3,4] to [-1,0] = 4 seconds
Total time = 7 seconds

Example 2:

Input: points = [[3,2],[-2,2]]
Output: 5

Constraints:

  • points.length == n
  • 1 <= n <= 100
  • points[i].length == 2
  • -1000 <= points[i][0], points[i][1] <= 1000

Python Solution

class Solution:
    def minTimeToVisitAllPoints(self, points: List[List[int]]) -> int:
        ans = 0
        for i in range(1, len(points)):
            prev, cur = points[i - 1 : i + 1]
            ans += max(map(abs, (prev[0] - cur[0], prev[1] - cur[1])))
        return ans   

Leave a Reply

Your email address will not be published. Required fields are marked *