【LeetCode】169. Majority Element Majority Element Given an array of size n, find the majority eleme

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.

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

 

每找出两个不同的element，则成对删除。最终剩下的一定就是所求的。

可扩展到⌊ n/k ⌋的情况，每k个不同的element进行成对删除。

证明可参见我在Discussion上的分析https://oj.leetcode.com/discuss/19151/solution-computation-space-problem-can-extended-situation

class Solution {public:    int majorityElement(vector<int>& nums) {        int candidate = 0;        int count = 0;        for(int i = 0; i < nums.size(); i ++)        {            if(count == 0)            {                candidate = nums[i];                count = 1;            }            else            {                if(nums[i] == candidate)                    count ++;                else                    count --;            }        }        return candidate;    }};