Learn AI Create the Future — with Pranay
Main site

LeetCode solutions

2116. Count Number of Pairs With Absolute Difference K

My accepted Python solution to LeetCode problem 2116, Count Number of Pairs With Absolute Difference K, running in 4ms.

  • Difficulty: Easy
  • Python
  • Runtime 4ms
  • Memory 17.1MB

Read the problem on LeetCode View on GitHub

The problem statement is LeetCode’s and stays on their site. What follows is my accepted solution.

Python

Accepted on LeetCode — runtime 4ms, memory 17.1MB, accepted 2025-12-29.

python
class Solution:
    def countKDifference(self, nums: List[int], k: int) -> int:
        # Use hash map to count: for each num, look for num-k and num+k
        # Time: O(n), Space: O(n)
        from collections import Counter
        count = Counter(nums)
        result = 0
        for num in count:
            if num + k in count:
                result += count[num] * count[num + k]
        return result

Source