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#include <iostream>
#include <vector>

class Solution {
public:
    std::vector<int> majorityElement(std::vector<int>& nums) {
        int num1, num2;
        int cnt1 = 0, cnt2 = 0;
        for (auto& n : nums) {
            if (cnt1 == 0) {
                num1 = n;
                cnt1 = 1;
            }
            else if (num1 == n) {
                ++cnt1;
            }
            else if (cnt2 == 0) {
                num2 = n;
                cnt2 = 1;
            }
            else if (num2 == n) {
                ++cnt2;
            }
            else {
                --cnt1;
                --cnt2;
                if (cnt1 == 0) {
                    std::swap(cnt1, cnt2);
                    std::swap(num1, num2);
                }
            }
        }
        
        cnt1 = cnt2 = 0;
        for (auto& n : nums) {
            if (n == num1) {
                ++cnt1;
            }
            else if (n == num2) {
                ++cnt2;
            }
        }
        
        int n = nums.size() / 3;
        std::vector<int> res;
        if (cnt1 > n) {
            res.push_back(num1);
        }
        if (cnt2 > n) {
            res.push_back(num2);
        }
        
        return res;
    }
};