Majority Element II

Given an integer array of size n, find all elements that appear more than⌊ n/3 ⌋ times. The algorithm should run in linear time and in O(1) space.

class Solution {
public:
    vector<int> majorityElement(vector<int>& nums) {
        vector<int> result;
        int n = nums.size();

        int num1 = nums[0], num2 = nums[0];
        int counter1 = 0;
        int counter2 = 0;

        for (int i = 0; i < n; i++)
        {
            if (counter1 == 0 || num1 == nums[i])
            {
                num1 = nums[i];
                counter1++;
            }
            else if (counter2 == 0 || num2 == nums[i])
            {
                num2 = nums[i];
                counter2++;
            }
            else
            {
                counter1--;
                counter2--;
            }
        }

        counter1 = 0;
        counter2 = 0;

        for (int i = 0; i < n; i++)
        {
            if (nums[i] == num1)
            {
                counter1++;
            }
            else if (nums[i] == num2)
            {
                counter2++;
            }
        }

        if (counter1 > n/3)
        {
            result.push_back(num1);
        }
        if (counter2 > n/3)
        {
            result.push_back(num2);
        }

        return result;
    }
};


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