How to Solve Leetcode Rectangle Overlap Problem

Perfect for beginners: learn how to approach the problem and implement a clean solution without overcomplicating it.

I failed this question in my interview, even though I had already solved it before. I couldn’t come up with the solution during the interview. After revisiting the problem, I identified the mistake I made, and in this article, I’ll explain the intuition and the correct solution.

Problem:

An axis-aligned rectangle is represented as a list [x1, y1, x2, y2], where (x1, y1) is the coordinate of its bottom-left corner, and (x2, y2) is the coordinate of its top-right corner. Its top and bottom edges are parallel to the X-axis, and its left and right edges are parallel to the Y-axis.

Two rectangles overlap if the area of their intersection is positive. To be clear, two rectangles that only touch at the corner or edges do not overlap.

Given two axis-aligned rectangles rec1 and rec2, return true if they overlap, otherwise return false.

Example:

Example 1:

Input: rec1 = [0,0,2,2], rec2 = [1,1,3,3]
Output: true
Example 2:

Input: rec1 = [0,0,1,1], rec2 = [1,0,2,1]
Output: false
Example 3:

Input: rec1 = [0,0,1,1], rec2…