LeetCode 169. Majority Element (Easy)

题目描述：

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.

题目大意：给出一个大小n的数组，找出“主要元素”：出现次数多于⌊ n/2 ⌋次的元素。

思路：哈希一下，再遍历哈希表即可。

c++代码：

class Solution {public:    int majorityElement(vector<int>& nums) {        map<int, int> hash;        for (auto i : nums)        {            hash[i]++;        }        int length = nums.size() % 2 == 0 ? nums.size() / 2 : (nums.size() + 1) / 2;        for (auto i : hash)        {            if (i.second >= length)            {                return i.first;            }        }    }};