<p>Given an integer array <code>nums</code>, return <em>the sum of divisors of the integers in that array that have exactly four divisors</em>. If there is no such integer in the array, return <code>0</code>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> nums = [21,4,7]
<strong>Output:</strong> 32
<strong>Explanation:</strong> 
21 has 4 divisors: 1, 3, 7, 21
4 has 3 divisors: 1, 2, 4
7 has 2 divisors: 1, 7
The answer is the sum of divisors of 21 only.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> nums = [21,21]
<strong>Output:</strong> 64
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> nums = [1,2,3,4,5]
<strong>Output:</strong> 0
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= nums.length &lt;= 10<sup>4</sup></code></li>
	<li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li>
</ul>


class Solution
{
public:
    int sumFourDivisors(vector<int> &nums)
    {
        int limit = *max_element(nums.begin(), nums.end());
        sort(nums.begin(), nums.end());

        const int idx = 1e7;
        int divisorsSum[idx + 2];
        int divisorscnt[idx + 2];

        for (int i = 0; i <= limit; i++)
        {
            divisorsSum[i] = 0;
            divisorscnt[i] = 0;
        }

        for (int i = 1; i <= limit; i++)
        {
            for (int j = i; j <= limit; j += i)
            {
                divisorsSum[j] += i;
                divisorscnt[j]++;
            }
        }

        int ans = 0;

        for (int i = 0; i < nums.size(); i++)
        {
            if (divisorscnt[nums[i]] == 4)
            {
                ans += divisorsSum[nums[i]];
            }
        }

        return ans;
    }
};
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