2006. Count Number of Pairs With Absolute Difference K

Easy

10 Points

Array

Hash Table

Counting

Given an integer array nums and an integer k, return the number of pairs (i, j) where i < j such that |nums[i] - nums[j]| == k. The value of |x| is defined as:

Examples

Example 1

Input: nums = [1,2,2,1], k = 1 Output: 4 Explanation: The pairs with an absolute difference of 1 are: - [1,2,2,1] - [1,2,2,1] - [1,2,2,1] - [1,2,2,1]

Example 2

Input: nums = [1,3], k = 3 Output: 0 Explanation: There are no pairs with an absolute difference of 3.

Example 3

Input: nums = [3,2,1,5,4], k = 2 Output: 3 Explanation: The pairs with an absolute difference of 2 are: - [3,2,1,5,4] - [3,2,1,5,4] - [3,2,1,5,4]

Constraints

1 <= nums.length <= 200
1 <= nums[i] <= 100
1 <= k <= 99