LC-0532 Medium LeetCode

532. K-diff Pairs in an Array

Array Hash Table Two Pointers Binary Search Sorting

Read the full problem statement on LeetCode.

Difficulty: medium Acceptance: 45% Topics: Array, Hash Table, Two Pointers, Binary Search, Sorting

Reading material

Arrays & Hashing 12 min Two Pointers 9 min Binary Search 12 min

Reference solution (spoiler · python)

# Time:  O(n)
# Space: O(n)

class Solution(object):
    def findPairs(self, nums, k):
        """
        :type nums: List[int]
        :type k: int
        :rtype: int
        """
        if k < 0: return 0
        result, lookup = set(), set()
        for num in nums:
            if num-k in lookup:
                result.add(num-k)
            if num+k in lookup:
                result.add(num)
            lookup.add(num)
        return len(result)

Solution from kamyu104/LeetCode-Solutions · MIT