[LeetCode 836] Rectangle Overlap

Given two rectangles, find if the given two rectangles overlap or not.

Notice

l1: Top Left coordinate of first rectangle.
r1: Bottom Right coordinate of first rectangle.
l2: Top Left coordinate of second rectangle.
r2: Bottom Right coordinate of second rectangle.

l1 != r2 and l2 != r2

Example

Given l1 = [0, 8], r1 = [8, 0], l2 = [6, 6], r2 = [10, 0], return true

Given l1 = [0, 8], r1 = [8, 0], l2 = [9, 6], r2 = [10, 0], return false

The solution itself does not worth noticing too much as it is really easy. The take away of this problem is when trying to check if a condition is true or false, we can do it in two ways. Either check if all the true conditions are met; Or check if all the false conditions are met.

For this problem, checking if the two given rectangles overlap directly is complicated. So we check if they do not overlap, then return the reversed check result.

 1 /**
 2  * Definition for a point.
 3  * class Point {
 4  *     public int x, y;
 5  *     public Point() { x = 0; y = 0; }
 6  *     public Point(int a, int b) { x = a; y = b; }
 7  * }
 8  */
 9 
10 public class Solution {
11     /**
12      * @param l1 top-left coordinate of first rectangle
13      * @param r1 bottom-right coordinate of first rectangle
14      * @param l2 top-left coordinate of second rectangle
15      * @param r2 bottom-right coordinate of second rectangle
16      * @return true if they are overlap or false
17      */
18     public boolean doOverlap(Point l1, Point r1, Point l2, Point r2) {
19         // Write your code here
20         return !(l1.x > r2.x || r1.x < l2.x || r1.y > l2.y || l1.y < r2.y);
21     }
22 }