数组中出现次数超过一半的数字

class Solution {public:int MoreThanHalfNum_Solution(vector<int> numbers) {if(numbers.size() == 0)            return 0;       map<int,int> m;        for(int i = 0; i < numbers.size(); i++){            if(m[numbers[i]] != NULL)            m[numbers[i]]++;            else                m[numbers[i]] = 1;            if(m[numbers[i]] * 2 > numbers.size())                return numbers[i];        }        return 0;}};