[Leetcode][python]Longest Consecutive Sequence/最长连续序列

class Solution(object):
    def longestConsecutive(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        numset, maxlen = set(nums), 0
        for n in set(nums):
            currlen = 1

            tmp = n + 1
            while tmp in numset:
                currlen += 1
                numset.discard(tmp)  # 删去
                tmp += 1

            tmp = n - 1
            while tmp in numset:
                currlen += 1
                numset.discard(tmp)
                tmp -= 1
            maxlen = max(maxlen, currlen)
        return maxlen