java.lang.Object
g0101_0200.s0128_longest_consecutive_sequence.Solution

public class Solution extends Object
128 - Longest Consecutive Sequence.

Medium

Given an unsorted array of integers nums, return the length of the longest consecutive elements sequence.

You must write an algorithm that runs in O(n) time.

Example 1:

Input: nums = [100,4,200,1,3,2]

Output: 4

Explanation: The longest consecutive elements sequence is [1, 2, 3, 4]. Therefore its length is 4.

Example 2:

Input: nums = [0,3,7,2,5,8,4,6,0,1]

Output: 9

Constraints:

  • 0 <= nums.length <= 105
  • -109 <= nums[i] <= 109
  • Constructor Details

    • Solution

      public Solution()
  • Method Details

    • longestConsecutive

      public int longestConsecutive(int[] nums)