题解 | #数组中出现次数超过一半的数字#

class Solution {
  public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     *
     * @param numbers int整型vector
     * @return int整型
     */
    int MoreThanHalfNum_Solution(vector<int>& numbers) {
        int res;
        map<int, int> m;
        for (int i = 0; i < numbers.size(); i++) {
            int key = numbers[i];
            int value;
            map<int, int>::iterator it = m.find(key);
            if (it == m.end()) {
                value = 1;
            } else {
                value = m[key] + 1;
            }
            m[key] = value;
        }
        double len_2 = numbers.size() / 2.0;

        for (map<int, int>::iterator it = m.begin(); it != m.end(); it++) {
            if(it->second > len_2) res = it->first;
        }

        return res;
    }
};

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