169. Majority Element：Python

169. Majority Element

Given an array of size n, find the majority element. The majority element is the element that appears more than ? n/2 ? times.

You may assume that the array is non-empty and the majority element always exist in the array.

思路：

将列表中的数值进行一个出现次数的统计，然后判断出现最多次数的元素次数是否满足条件，是则输出。（这里用了2个for循环，效率不是很高，提交时速度只打败了50%不到的其他提交者，还有很大改进的余地）

代码：

class Solution:
    def majorityElement(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        dic = {}
        for i in range(len(nums)):
            if nums[i] in dic:
                dic[nums[i]] += 1
            else:
                dic[nums[i]] = 1

        HighValue = 0
        HighKey = None
        for each in dic:
            if dic[each] > HighValue:
                HighValue = dic[each]
                HighKey = each
        if HighValue>len(nums)//2:
            return HighKey