Largest Consecutive Sequence

Given an unsorted integer array, find the length of the longest consecutive elements sequence. The input consists of a single line with space-separated integers. The output should be a single integer representing the length of the longest consecutive sequence. Example: Input: 100 4 200 1 3 2 Output: 4 Explanation: The longest consecutive sequence is [1, 2, 3, 4], which has a length of 4.