[leetcode 229]Majority Element II

Given an integer array of size n, find all elements that appear more than ⌊ n/3 ⌋ times. The algorithm should run in linear time and in O(1) space.
Hint:
How many majority elements could it possibly have?
Do you have a better hint? Suggest it!

记录在数组中出现次数最多的两个元素，然后判断这两个元素是不是出现次数超过n/3

AC代码

class Solution {public:    vector<int> majorityElement(vector<int>& nums) {     int sum=nums.size();     if(sum<=1)        return nums;     vector<int> res;     int temp1=0;     int count1=0;     int temp2=0;     int count2=0;     for(int i=0;i<sum;++i)     {         if(count1==0||nums[i]==temp1)             {                 ++count1;                 temp1=nums[i];             }         else if(count2==0||nums[i]==temp2)            {                ++count2;                temp2=nums[i];            }         else         {             --count1;             --count2;         }     }     int sum1=0;     int sum2=0;     for(int i=0;i<sum;++i)     {         if(nums[i]==temp1)            ++sum1;         else if(nums[i]==temp2)            ++sum2;         else            continue;     }     if(sum1>sum/3)        res.push_back(temp1);     if(sum2>sum/3)        res.push_back(temp2);     return res;    }};

其他Leetcode题目AC代码：https://github.com/PoughER/leetcode