【Daily Code】leetcode 1287 C++

class Solution {
public:
    int findSpecialInteger(vector<int>& arr) {
        vector<int> v(100000 + 10, 0);
        int l = arr.size();
        for(int i = 0; i < l ; i ++) {
            v[arr[i]] ++;
            if(v[arr[i]] * 4 > l) return arr[i];
        }
        return -1;
    }
};