majority element

 纪录一个数，初始为1，相同则数量＋1否则－1；

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