‹ DS&A interview · Socratic
DSA · Geometry / Hash Map · #110

Max Points on a Line

Module 74 · difficulty 4/5·30:00starts on first keystroke

Given an array `points` where `points[i] = [xi, yi]` represents a point on the X-Y plane, return the maximum number of points that lie on the same straight line. Implement the function `maxPoints(points)` that returns this integer.

Examples
  • points = [[1,1],[2,2],[3,3]] 3All three points are collinear on the line y = x.
  • points = [[1,1],[3,2],[5,3],[4,1],[2,3],[1,4]] 4The line through (1,1), (3,2), (5,3) plus one more aligned point gives 4.
  • points = [[0,0]] 1A single point trivially lies on a line by itself.
Constraints
  • · 1 <= points.length <= 300
  • · points[i].length == 2
  • · -10^4 <= xi, yi <= 10^4
  • · All the points are unique.
Session phases
A · Clarify
B · Approach
C · Complexity
D · Edges
E · Code
F · Tradeoff
G · Score
Phase A — Clarify
Ask questions about input bounds, types, and edge constraints.
Ask the coach clarifying questions about the problem.
When you've covered this phase, advance to the next.