Longest Consecutive Sequence
Find the length of the longest consecutive elements sequence in O(n) time.

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Longest Consecutive Sequence
medium
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Find the length of the longest consecutive elements sequence in O(n) time.

Example 1:
Input: [100,4,200,1,3,2]
Output: 4
Constraints:

  • 0≤nums.length≤1050 \leq \text{nums.length} \leq 10^5

  • −109≤nums[i]≤109-10^9 \leq \text{nums}[i] \leq 10^9

Input
arr =[100,4,200,1,3,2]
Current Longest

0

Input Array
100
4
200
1
3
2
HashSet (O(1) Lookup)
100
4
200
1
3
2
Building Sequence
No active sequence
Variables
VariableValue
longest0
DepthFunction Call
Stack empty
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