leetcode_majority_elements_ii

class Solution {
public:
    vector<int> majorityElement(vector<int>& nums) {
        if(nums.size() == 0)    return vector<int>();
        int m = 0,n = 0,cm = 0,cn = 0;
        for(int i = 0; i < nums.size(); i++)
        {
            if(nums[i] == m) cm++;
            else if(nums[i] == n) cn++;
            else if(nums[i] != m && cm == 0) m=nums[i],cm=1;
            else if(nums[i] != n && cn == 0) n=nums[i],cn=1;
            else cm--,cn--;
        }
        // cout<<m<<" "<<n<<endl;
        cm = 0;
        cn = 0;
        for(int i = 0; i < nums.size(); i++)
        {
            if(nums[i] == m)
                cm++;
            else if(nums[i] == n)
                cn++;
        }
        // cout<<cm<<" "<<cn<<endl;
        vector<int>ret;
        if(cm > nums.size()/3)
            ret.push_back(m);
        if(cn > nums.size()/3)
            ret.push_back(n);
        return ret;
    }
};