LeetCode——Majority Element

LeetCode——Majority Element

# 169

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.

Credits:
Special thanks to @ts for adding this problem and creating all test cases.

这一题的目的是找出数组中的majority element，就是出现超过数组个数一半的元素。这一题一看到，就有两个方法，一个是暴力求解，一个是利用hash表。暴力求解就是两个循环，写一下hash表的方法。

• C++

class Solution {public:    int majorityElement(vector<int>& nums) {        if(nums.size() == 0)            return 0;        unordered_map<int,int> m;        for(int i = 0;i < nums.size();i++) {            if(m[nums[i]] == NULL)                m[nums[i]] = 1;            else                m[nums[i]]++;            if(m[nums[i]] > (nums.size()/2))                return nums[i];        }        return 0;    }};

这一题看了下LeetCode上的方法，足足有6种，我粗略的看了下。觉得有点算法用到这上面，有点大材小用。后面的题目如果使用到，就再记录吧。