Find K-th Smallest Pair Distance

arraytwo pointersbinary search

Problem Statement

The distance of a pair of integers a and b is defined as the absolute difference between a and b .

Given an integer array nums and an integer k , return the k ^th smallest distance among all the pairs nums[i] and nums[j] where 0 <= i < j < nums.length .

Examples

Example 1

Input: nums = [1,3,1], k = 1
Output: 0
Here are all the pairs:
(1,3) -> 2
(1,1) -> 0
(3,1) -> 2
Then the 1 ^st smallest distance pair is (1,1), and its distance is 0.

Example 2

Input: nums = [1,1,1], k = 2
Output: 0

Example 3

Input: nums = [1,6,1], k = 3
Output: 5

Constraints

n == nums.length

2 <= n <= 10 ^4

0 <= nums[i] <= 10 ^6

1 <= k <= n * (n - 1) / 2

😤

Hard

Difficulty

Topic Info

ModuleDSA

CategoryArray

Sub-topicTwo Pointers