[Python知识库]最长连续序列-数组128-python

并查集：在一些有N个元素的集合应用问题中，我们通常是在开始时让每个元素构成一个单元素的集合，然后按一定顺序将属于同一组的元素所在的集合合并。

python

class Solution:
    def longestConsecutive(self, arr: List[int]):
        n = len(arr)
        res = 0
        dic = {}

        for data in arr:
            tmp = 0
            if data not in dic.keys():
                tmp1, tmp2 = 0, 0
                dic[data] = 1
                if data-1 in dic.keys():
                    tmp1 = dic[data-1]
                if data+1 in dic.keys():
                    tmp2 = dic[data+1]
                tmp = tmp1 + tmp2 + 1
                dic[data-tmp1] = tmp
                dic[data+tmp2] = tmp
                res = max(res, tmp)
        
        return res